sorry you need to read up on the magneto ignition system, the points dont stay open most of tbe time and the condenser does not feed current back through the primary coil
Now I'm really confused I thought the points were closed most of the time and they opened momentarily for the power to travel to the plug instead of ground.
They are closed most of the time, they open momentarily at whatever degrees before tdc. This collapses the magnetic field creating the high voltage current...creating the spark....so you are right Garry.....he's wrong....!
@@deanhenthorn1890 I have this same engine and the points are OPEN most of the time. I've seen a few engines that work like this including the Onan engines. My understanding is that either system can work to break the electrical field and cause the energy to pass through the secondary winding and through the spark plug to ground.
Thanks for the video. Good stuff and a generally clear explanation. I feel you may have got CDI and points ignition systems somewhat confused. What you may find happens is that the current generated as a double and reversed wave ( as you pointed out) is allowed to flow through the points to ground creating a circuit. This circuit is broken by the points at the peak of the second wave, The condenser does stop arcing but more than just to save the points it precipitates a sharp instantaneous collapse of the magnetic field and it is this which generates the massively high voltage in the secondary coil. Keep up the excellent work I love your tips!
My thoughts as well, until later in the video he shows a points system I haven't seen, a bit different to a motorcycle or car but yes, is points, well... a single point lol
you have an error in your explanation there is no current flowing thru the points the points open lifts a gd off the condenser lead allowing a current flow thru the primary coil thru the condenser to gd via the metal can and screw to the base of dist this flow creares ahigh voltage in sec . coil sending it to dist cao and plugs as points closecond lead is gd again stopping voltage the only time points have current is either wrong condenser or defect condenser the voltage can not get thru the cond.so it jumps the tiny gap at open points to gd which causes pitting of the points over time you can test this with your voltmeter conn to the cond lead with switch in run pos you will see batter volts (12) on that screw now open the points the voltage falls off. hope this helps some one most of the time the condenser is failing if you have spark tbls.
@@frankdavidson9675 Either you don't know what you're talking about or you need to take a writing class so you can effectively put your thoughts and ideas on paper for people to understand. I know conventional ignition systems (points and condenser) like the back of my hand and I have trouble understanding what you wrote.
Great explanation on points, ignition system!!! I have a Wheel Horse that I bough new in 1976 that has points. Years back I pulled the flywheel only to find that the points are conveniently located on the block. Can’t beat experience or having a manual :)
Do you really have a 'dent' in your crankshaft ? Normally there's a 'bulge', because the secondary circuit gets activated when the points open, not close as you say! Or is this only with battery equipped systems? Does this system work the other way around than normal? please clarify, some1...
This seems to show the spark plug fires every stroke but it seems a four stroke should fire every other stroke. I suppose it could fire right at tdc of the intake stroke also and it wouldn't affect anything?
I have a TecumsehH540 or HS40 and the points are closed all the time until a lobe on the crank open them up for a few degrees of rotation, seems backwards from what you say being open 90% of the time, either way, no spark and while points are open no resistance from the open point to ground, I haven't worked with points for 30 years so I forgot alot. Any ideas on how to test? Nice Vid!
I do have a video on swapping these th-cam.com/video/HV9MJwsUP_4/w-d-xo.html but your already in so may not help much. The most common, no spark culprit in order is: dirty/greasy/corroded point connection that don't make a good connection, the ground kill wire still engaged, dead condensor, shorting out the spark, and finally a dead ignition coil. So I always like to pull the kill wire off the kill location from under the carb to eliminate it. Then I run some fine sand paper(300+) through the points and spray then off with carb cleaner or brake cleaner to degrease them. Then I try to get a spark.
Thank you and Well done........I have a Puch moped........the ignition system incorporates a "kill switch" fitted to the handlebars...........wil this basically be a open circuit or a grounded circuit, to/from the coil ? Thanks
A day that you don't learn something is a day wasted. I have picked up a lot of information and you have jogged my memory every now and then. Thank you!
Thanks for the video. I've got a little 2 hp Briggs 60102 and after it started running lean and dying on me, I decided to replace all of the gaskets (intake, gas tank, crankcase, valve cover, and even the head gasket). I had adjusted to carb with no luck, so I figured I'd just do a little overhaul since the gaskets were cheap enough. I checked the points and condenser and all seemed really clean plus no cracks on the top of the condenser. I sanded the points and set the gap to 20 thousandths, although they were pretty clean to begin with and the gap was at 22 thousandths before. I fired it back up and it will run quite well at half throttle and idle pretty good, but will sputter and want to quit at full throttle. Tried adjusting the carb both directions with no luck. I would assume my points and condenser are fine if it runs so consistently at half throttle, but thought I'd run it by you to see what you think. I just regapped the spark plug, but figure I could replace that just to eliminate it as a cause.
tlgrimmy Sounds carb related. The fuel pickup tube that drops into the tank can become blocked. It has a fine mesh screen and it can become blocked if you have a rusty gas tank. Before this I would make sure the Main Jet is clean by unscrewing the nut+screw as an assembly. Then remove the Jet with a wide flat head screwdriver. Spray carb cleaner through this. Inside the carb hole that your pulled the Jet out of there are some holes behind where this jet sat; clean those as well. Generally if the engine sparks then it sparks and doesn't change with RPM; if anything it gets stronger with speed.
sixtyfiveford Thanks for getting back to me so quickly, much appreciated! After reading your response, I pulled the needle and jet, cleaned everything up thoroughly as you mentioned and then I noticed that the needle had a bur on it that I hadn't seen before. It looked as if it had been screwed in all the way and tightened down enough to ruin the taper on the needle and create a bur. That makes sense of the issue with the needle not making much difference on gas flow, as that bur was probably restricting flow. I chucked it in my drill press and carefully filed away the bur and polished things back up. I put it all back together and viola! It runs infinitely better now. I did end up having to keep the needle out only 1 turn due to shortening it when I filed it down, but at least I found the culprit. I'll go ahead and buy a new needle and jet just to get it at it's best though. Thanks again for pointing me in the right direction, that really helped! Feels good to have the problem finally solved.
That's great. Keep in mind that it really isn't important how many turns out you go. The 1.5 turns is just a number to get the machine running but it needs to be fine tuned from there. At full throttle turn it in slightly until it begins to stumbles then out until the same occurs. Set it to the middle of these readings and maybe even 1/8+- of a turn out.
Your video was excellent, I have question about a 1975 16 hp Briggs engine as to where the magnet wire wire From the ignition switch is connected , is yellow wire or m wire hook to the points Thank you Jim
I hate to tell ya buddy but you have it backwards….The points stay closed most of the time as the primary coil is being charged up.The moment the points open up, the primary field collapses inducing a current in the secondary winding which goes down to the spark plug firing it off. The condenser does stop the points from arcing a lot, that is true.
A few days ago I was digging int o a small 5 horse Briggs that had no spark. And the points actually do stay open most of the time and close very briefly. I'm so confused because with literally every other points I have experience it's the other way around. And I still don't know if it's supposed to be like that.
Even on youtube will see video's by mechanics, auto electricians and others who have absolutely no idea that the condenser (capacitor) boosts the secondary voltage. Good video.
How can the condenser send current back through the primary while there is no return path to ground. The points open, which breaks the ground. The magnetic field collapses causing current in the secondary. Once the points close again, the stored current is fed back into the primary and helps boost the next cycle. Current cannot flow without a ground or am I missing something here?
Hard to explain without a video or drawings. Some sites miss out on some details. The information you are looking for must mention the condensor absorbs the points spark but also provides the reverse direction current required to generate the high voltage. Try th-cam.com/video/W94iksaQwUo/w-d-xo.html
Thanks for the reply. I've been looking online to see how exactly this works being as there is no path to ground while the points are open. The condenser is grounded, so maybe it's just in the way the condenser is made?
I found the answer :-) Once the field collapses in the primary winding's, the voltage stored in the condenser is higher than what's in the primary circuit. The insulated foil sheet inside the condenser forces the stored voltage back through the primary winding's, which makes for a longer duration spark at the plug. This keeps happening until all the stored voltage is used up. I had to search a lot of old books to find this info. Finally found it in a auto fundamental's book from 1960. Thanks for the thought provoking reply :-)
Very informative thanks . I have a 1978 Bultaco Sherpa 250. Can't seem to get it to run right, it'll run at full pelt or not at all. Think I might have wired the primery ciol up wrong or may have a short some where. are the Primery and the condeser bolted to the engine ( to ground ) or are they insulated in some ay
A secondary tap of the coil provides a signal to do many things prior to hi voltage rectification for the spark plug. Many people are looking for passive analog devices to support electrical needs sans onboard battery.
Just a quick question the new points I installed for my Kohler K321. If I can see a bright spark when the motor is turning over would this indicate a bad condenser? Thanks for posting the video.
What about magnetos for twin cylinder engines? I believe the secondary coil is not grounded by a coil tap and only grounds by arcing across both spark plugs.
Your explanation is incorrect. Wikipedia better explains: In the type known as a shuttle magneto, the engine rotates a coil of wire between the poles of a magnet. In the inductor magneto, the magnet is rotated and the coil remains stationary. As the magnet moves with respect to the coil, the magnetic flux linkage of the coil changes. This induces an EMF in the coil, which in turn causes a current to flow. One or more times per revolution, just as the magnet pole moves away from the coil and the magnetic flux begins to decrease, a cam opens the contact breaker and interrupts the current. This causes the electromagnetic field in the primary coil to collapse rapidly. As the field collapses rapidly there is a large voltage induced (as described by Faraday's Law) across the primary coil. As the points begin to open, point spacing is initially such that the voltage across the primary coil would arc across the points. A capacitor is placed across the points which absorbs the energy stored in the leakage inductance of the primary coil, and slows the rise time of the primary winding voltage to allow the points to open fully.[5] The capacitor's function is similar to that of a snubber as found in a flyback converter. A second coil, with many more turns than the primary, is wound on the same iron core to form an electrical transformer. The ratio of turns in the secondary winding to the number of turns in the primary winding, is called the turns ratio. Voltage across the primary coil results in a proportional voltage being induced across the secondary winding of the coil. The turns ratio between the primary and secondary coil is selected so that the voltage across the secondary reaches a very high value, enough to arc across the gap of the spark plug. As the voltage of the primary winding rises to several hundred volts,[5][6] the voltage on the secondary winding rises to several tens of thousands of volts, since the secondary winding typically has 100 times as many turns as the primary winding.[5] The capacitor and the coil together form a resonant circuit which allows the energy to oscillate from the capacitor to the coil and back again. Due to the inevitable losses in the system, this oscillation decays fairly rapidly. This dissipates the energy that was stored in the condenser in time for the next closure of the points, leaving the condenser discharged and ready to repeat the cycle. On more advanced magnetos the cam ring can be rotated by an external linkage to alter the ignition timing. In a modern installation, the magneto only has a single low tension winding which is connected to an external ignition coil which not only has a low tension winding, but also a secondary winding of many thousands of turns to deliver the high voltage required for the spark plug(s). Such a system is known as an "energy transfer" ignition system. Initially this was done because it was easier to provide good insulation for the secondary winding of an external coil than it was in a coil buried in the construction of the magneto (early magnetos had the coil assembly externally to the rotating parts to make them easier to insulate-at the expense of efficiency). In more modern times, insulation materials have improved to the point where constructing self-contained magnetos is relatively easy, but energy transfer systems are still used where the ultimate in reliability is required such as in aviation engines. Edit
You can use a capacitance tester to test the mfd. However most people don't have one of those so, in that case it's easiest to just replace the condenser if it is over 10years old(though I have seen them go 40+ years without issue)
@@sixtyfiveford hmmmm. I have a mcculloch eager beaver top handle chainsaw.. spark isn’t the greatest so it doesn’t start. I’m thinking it’s due to the condenser/capacitor. My multimeter read 1 microfarad but I’m not sure if it’s within spec as the capacitor doesn’t have any labeling on it.. I did read online that most chainsaw capacitors read .22mfd. If that info is correct, mine is wayyyyy out of spec! Would getting a condenser designed for cars and similar in size work? Trying to avoid paying the $30 for an old brand name McCulloch condenser when I can just pay a few bucks for a generic brand from the auto parts store..
@@berniemac8413 I have swapped condensers many times. Most of the time I use the cheapest Briggs and Stratton ones but they might not fit into a chainsaw. But have never had an issue swapping them around.
I have a Wisconsin Engine on a Essick Plaster mixer, I was told once a magneto gets wet it ruins it. I wish you could show the points or magneto. Q. Is the transformer & Magneto the same?
Time to go back to school. The points stay CLOSED most of the time. When the points OPEN momentarily, The field collapses at that point, and the magic happens. Careful what you tell folks.
We should just leave it as "It's magic" instead of people trying to explain the magic "as they understand it"...besides this is old magic that most people will never witness as we have new magic nowadays.
mon0railbredpig Yes the plug fires every intake/compression cycle and exhaust cycle but this has no ill effect, in fact it has no effect during the exhaust because there is nothing to burn.
Great explanation! Thanks! In order to obtain a very HIGH VOLTAGE in the secondary, we need a GREAT FLUX CHANGE through the core (implicitly secondary coil), because the greater the flux change the greater the voltage obtained. Therefore, besides collapsing the flux in the primary, we ALSO REVERSE the current direction through it, obtaining a GREATER FLUX DECAY through the primary, and this is exactly what the capacitor does. A capacitor always opposes a build up in voltage by charging itself. The contactor circuit here shortens both the primary coil and the capacitor. The capacitor opposes the build up of the induced voltage in the primary by charging up, and immediately after the circuit opens (10 degrees after Neutral, EGAP), the capacitor is no longer shortened by the contactor, so it discharges solely through the primary coil. Keep in mind, that any collapsing magnetic field through a coil, give rise to a self induced current through that coil. In our case, the self induced current due to the collapsing magnetic field is opposed by the capacitor current through the primary, thus hurrying up the collapse (according to the Right-Hand Corkscrew Rule) ! In other words, the capacitor only forces a reversed current through the primary, to oppose the selfinduced one, in the end accelerating the collapse of the induced magnetic field. This happens very quickly, right after 10 degrees past Neutral (EGAP). At this point, the CHANGE of the rotor magnetic field in the core is just below peak value, which means the EMFs generated in both the primary and secondary coils are just below maximum. Also, the CHANGES in the rotor magnetic field and the collapsing primary field have the same directions (very important)! As the two magnetic fields have the same direction of change, they will superimpose, thus give rise to a LARGE FLUX CHANGE through the core, implicitly through the secondary coil. This is like a spike in the magnetic flux change through it, leading to a very high EMF at the ends of the secondary, which translates in a spark obtained at the sparkplug. Moreover the capacitor and primary coil form a tuned LC circuit. All this starts when the EGAP commences and up to the point when N reaches the yoke (Full Register position), the superimposed flux change being large enough to create the spark. th-cam.com/video/OMLSNwQiiKg/w-d-xo.html
Make sure the kill wire isn't engaged. This can be with a key switch or throttle set to low. It's probably best just to disconnect it from under the carburetor and let it dangle out of the way.
i fitted a stihl points type ignition plate in an old echo saw... got NO SPARK until turning in wrong direction and then big blue spark.....checked position of strongest magnet and cut a keyway to get magnet leaving 2nd armature end as points open.... now sparks but weaker. strange as the stihl was anticlockwise rotation and echo is anticlockwise rotation....
I've swapped non-points Echo trimmer coil into a old points Poulan saw and it fired right up and I use it still. I know that the position of the magnets can be either North inwards/South outwards or South inwards/North outwards. If the coil is setup to pull off of North and it is in the inward position, it is like having a 3/4in flywheel to coil gap, which will give a weak spark. Briggs and Stratton had issues when they went from points to breakerless and flipped the polarity of the magnets in the flywheel. Customers were so mad they offered to repolarize the flywheel for free so people could put breakerless coils on their points machines. Later they switched back to the standard they were using before.
Really appreciate this information. I have a Tecumseh H50 that I'm trying to get running and couldn't wrap my head around how the ignition worked. Thank you!
I just bought a used Toro groundmaster 52(1979) it was running well and cut beautifully. It died while I had been cutting for about 1.5. It will turn over, but no spark. Have changed the armature, did as instructed on your video re condenser and point, checked to see if any wires in harness broken extra, but still no consistant spark, only once in a blue moon. Any ideas. Seat kill switch as been bypassed.. thxs
conwald1 This is the point system you have th-cam.com/video/QQqhvA5qo2c/w-d-xo.html . You can pull the kill wire all together to make sure it's not grounding out.
sixtyfiveford Mine is screwed, if you take off the kill swich, it will not turn over.. hook it back up, it will turn over. So something is wired backwards. Trying to find a new points and condensor, having a hard time. Looking at maybe the solonoid.
The points and condensor are easily obtainable from hundreds of online places. Don't search for them under Toro as they have nothing to due with Briggs and Stratton. The wire going from the coil to the points needs to stay in order to run, but the wire running from the points the tractor can be pulled off to test(kill wire). If you're getting intermittent spark more than likely you just need to sand the points with a very fine sand paper.
sixtyfiveford this is the problem, its backwards on our tractor. When we disconnect the wire from the points to the tractor it will not run. It will not even turn over, its absolutely dead. Connect it again and it cranks. Go figure. We are totally baffled.
Let me explain a little more clearly as I may have misdirected you a little. There are 2 wires coming from under the flywheel going to the coil. One goes to the points and the other comes out and is next to this wire but never touches the points. This is your kill wire and will go up into the loom to the ignition switch and all your safety kill wires touch this single wire. This is the only way the ignition is shorted out. You can simply unplug or temporarily cut this wire to eliminate the possibility the safety switches on the mower aren't killing it.
+sixtyfiveford Thanks for your quick response! I am getting spark at the plug and a constant spark at the points. The motor does start but won't stay running at low idle unless I open the points all the way but then it won't keep running at fast idle it skips and misses and eventually stalls. When I set the points to max (they are only supposed to be .020 for this K321) I get a brighter spark both at the points and the plug maybe that's why it stays running then? Any thoughts?
I have rebuilt the carb and adjusted it to the manual and them some to try and keep it running when I set the points to .020. If I set the points to full open It idles great at low rpm but won't run smooth at high rpms. Thank you for you thoughts!
I have to ask I have a vintage dirt bike and I just replaced the points and condenser and it's still sparking at the points when not running so do you know what the issue is? Thanks
+sixtyfiveford I checked that and changed the condenser and points so I'm not sure the book says it should read 5.9 ohms at the coil (spark plug) but I'm reading 10.25 ohms I'm not sure if they add up or not
Thanks for the excellent video! ...two questions: 1) Is the spark plug mounted above the EXACT center of the piston on top of a combustion chamber. 2) Also, at TDC, how far from the piston is the bottom of the plug? This information will be of GREAT help! Thanks much,
the plug can be any where in the head as long as it not touching any thing look at it this way on compresion stroke you can light it with a spark any where
Great simple overview and explanation. I can and have done mechanical repairs but the electronic parts have always been a bit of mystery to me..........Thanks again.
I have a small engine with this, and I get power to the top of the plug, but no spark. I put the plug in another engine and it has spark. I cleaned the points and the coil seems to be working (idk how he tested it). What would anybody suggest?
Too wonderful in your detailing. But I am still having difficulty of no spark in a very old Kohler engine Cleaned the points but still no spark not sure of condenser but as you say they rarely go. I must still have a bad condenser.
The condensers do go bad, just not as often as the point contacts. If a quick clean of the points doesn't restore points, I generally put a new condenser in.
Check to make sure the wire between the primary and the condenser is not shorted out against the engine block. Sometimes if the wire accidently touches the hot engine block, the insulation melts and causes a short circuit that prevents the coil from charging the condenser. Found this out the other day when replacing a condenser on an old Montgomery Ward generator.
Great vid... Would love to see if you come across points failing in leaf blowers. I've had two blowers go bad (no spark) in 2 years. The latest was a Poulan. Noticing on youtube a lot of the poulan leaf blowers are failing for different reasons.
Hi great video. Wondering if anyone can help me. Kohler 8hp K181 . Replaced coil, still no spark. I am thinking I probably should have ordered a condenser also. By the way only way for me to find parts is EBay, straight from China of course so just hoping they are good. Anyway in Checking the condenser, I am on 20k ohm setting, Red probe to wire, black too body, meter just stays at 1, should I not see a certain ohm reading, meaning I am charging the condenser? Also I would then check dc volts I believe, what am I looking for MV of something , then voltage should drop? Thanks for any help.
The condensor needs to be disconnected to test and should read around 30mfd from the body to the nipple. The coil is very very rarely the issue in lack of spark instances and generally dirty points, followed by failed condensor are the issue.
sixtyfiveford hey thanks so much for getting back to me. In my case a new coil fixed my no spark, but back to my original problem I had before loosing spark. For a couple years now I have been having the same thing. Runs great for anywhere from 15min to an hour then starts running rough. Let it cool and starts the same process. I just put on a spark tester and spark looks intermittent when running rough. I took a video but not sure if I can attach it. Could that be a condenser? I have ordered one don’t have it yet.
@@rltkktlr Absolutely I would replace the condensor. It is a wear item and over time won't hold the spark energy needed to collapse the field and create a spark.
sixtyfiveford ok got the parts, points and condenser, replace condenser, I certainly would have replaced the points but got lazy, it’s on a walk(push hard) behind leaf blower and blower would have had to come off get to points. Maybe a 1 inch screwdriver which I don’t have. So anyway condenser didn’t fix it so I threw in the towel bought a electronic conversion chip, $30, very easy to install, no more points and condenser, and great spark and runs great. Thanks again, great channel you have.
Don’t need North and south poles on flywheel only one polarity. When the magnet passes the magnetic field collapses and induces a voltage to secondary weather AC or DC it’s the same. Grounding the primary should not cause the spark to open, if so please explain the path for current.
what r symptoms of weak spark I have a old Neptune Outboard it don't wanna jump the spark across the spark pulg but when I hold the spark plug wire with my hand to ground I get a shock
sixtyfiveford I cleaned the points so it probably the condenser like u said ima just replace them both thank for the tips an reply grate video by the way
Excellent explanation - I’m confused at how grounding the primary circuit stops production magnetism since the fly wheel is still spinning wouldn’t the voltage still be induced into the primary? Current would flow from the grounded primary to the other side of the primary completing a circuit. I know clearly I’m wrong I just don’t understand. I want to add, I don’t think the magnets on the fly wheel need to have both positive and negative polarities, if we look at a coil pack on modern engines they use the 12VDC from the battery to operate. All we need is a magnetic spinning on the flywheel to cut flux into the primary coil. Grounding the secondary makes perfect sense to shunt the spark back to the coil but also raises another question - when doing so wouldn’t the current from shorting to ground be high due to the voltage being extremely high? I would think the secondary’s coil would short out.
+sixtyfiveford . I have an suzuki dt 7.5 outboard motor. I've loads of petrol and compression and some spark. I've put new points and reed valves and two new original plugs. still won't start. any ideas.
You should be able to run a spark test and get the spark to jump a 1/4" gap. This will ensure a strong enough spark to run. 2 strokes are easily flooded with too much fuel, to clear the fuel, pull it over a few dozen times with the plugs removed(choke off full throttle).
nice video I just start working on small engines I pick a 12 hp Tecumseh with points in the side of the block and condenser beside the coil and am just getting really weak spark because somebody pull all the wire from the points will appreciate some help
The primary collapses. The secondary does not collapse. When the primary collapses, a high voltage is induced in the secondary, and this induced high voltage is what creates the spark.
Hello, I was very pleased with your explanation on how dynamo ignition works, didn't have a clue until viewing your videao. Maybe a stupid question but I'm wondering, how high should the secondary voltage (feeding the spark plug) be? Would that be like hundreds- or thousands of volts? Up until now, haven't risked to test it.... maybe for the best..... Kind regards, Jacques Belgium. So as you can see you've got viewers all over the world although Belgium is a small European Country.
Thanks for this :) been working on making a Honda CG125 run off it's own steam with no lights or main loom or anything as a fun little flat tracker project and whilst I kinda knew what to do, I've never had a points bike before so this confirmed everything for me :)
Hello sixtyfiveford@@@ I was wondering if you can help me with my problem I have a ruggerini small engine that it's working but the condenser it's about to run out due to the wire it's coming a parts from it, I was wondering if all the condensers works the same because I just can't find the condenser for this engine please help
sixtyfiveford thanks alot for sharing this with me I was just wondering because I have one new setting there so it's the one should be doing the job next
Hey man, I have been wondering for a while now how to sort the mystery of this system as I bought a 1978 Honda CB550k. This really clarified it, and I'm sure I'll watch it a few times. Thanks!!
A-4 cycle engine needs a spark every other revolution. It looks like this will provide a spark each revolution like a 2-cycle engine. How do we account for this?
Can it be done if the coil is on the inside of the flywheel. I haven't been able to find a Vid. that covers my problem. The coil is on the inside of the wheel
So what is the mechanism to insure the exact microsecond of spark without points (now that I think about it); is it the more exact manufacturing so they know exactly when that mag field will collapse creating the surge of current in the primary thus secondary coil to spk plug? FYI: Model T's & i think A's had a separate coil for each cyl? so that if the key was on, the coil on tap would just sit there and keep sparking indefinitely . I found a condenser believe it or not from the old days "60's"
I'm a female and I love this stuff!!..... ;D I have a 5hp tecmsh that starts inconsistently.......I cleaned the carb and replaced o rings, etc......but am still having probs......my next task is to check the points, condenser and coil..... THANX!!
sbecktacular Awesome. The coil will either work or it won't but the points/condenser can be intermittent. I'm sure you saw I have a video on them th-cam.com/video/HV9MJwsUP_4/w-d-xo.html
hey thanx!... turns out my motor doesn't have points it has the magnetron? coil......I did alittle fiddlin' with it this morning and it's running GREAT! thankyou for all your informative vidz....much appreciated!
@@sixtyfiveford well also because I built a see through engine out of it like warped perception did and I used a screw in place of the spark plug where the spark jumps from the tip of the screw to the engine block in the combustion chamber between the valves and piston so a lot of exposed metal.
seems to be some confusion about points ---with points closed nothing is happening every thing is grounded when they open it removes the ground so current flows thru cond. to ground that flow going thru coil creates high voltage due to turns ratio of windings causing spark
no, sorry, direct current, the + end of the magnet drags the e- in one direction, and the - end pushes the e- as IT passes by. capacitors can ONLY STORE DC. But you were close.
65!! I love your banner!! Excellent explanation of how the entire ignition system works on a magneto engine!! Where did you get your banner made? Cheers!! Zip~
Nice info :) you do a great course in misc great stuff to know if you like to fix and work on stuff. ... you can use that if you wanna lol. I've got a Walmart Mower that's been great, but it's totally different than anything I ever saw, baffling a bit, but I better figure it out cause grass will be coming soon.
Your close but mostly wrong. At the precise moment the points open (not close) the ground is broken which causes the field in the coil to collapse and go to ground through the spark plug. The purpose of the condenser in layman’s terms is to protect the points by absorbing-the excess spark that would jump the points to ground and weld them when the field collapses. Nice video.
Smashing video :-)) Hmm i allways thought the capacitor and primary were like a tuned circuit and produced a stable magnetic field, then when the points closed the sudden loss made the primary over react (as charged inductors dont like change) and create a spike of intense magnitism trying to counteract the loss and firing the secondary. Looks like i may have been wrong :-(( Inductors do react to losses though, they do have some very odd propertys lol.
As a guy who likes taking care of his own equipment these type of tips are invaluable, thanks for spending the time to teach.
Thanks.. It's old technology but still out there.
Best explanation for condensers, coils and points on small engines. I've had to replace condensers on old lawnmowers and generators over the years.
Hey Thanks. I'm glad you liked it.
sorry you need to read up on the magneto ignition system, the points dont stay open most of tbe time and the condenser does not feed current back through the primary coil
You need to do a follow up vid
Now I'm really confused
I thought the points were closed most of the time and they opened momentarily for the power to travel to the plug instead of ground.
They are closed most of the time, they open momentarily at whatever degrees before tdc. This collapses the magnetic field creating the high voltage current...creating the spark....so you are right Garry.....he's wrong....!
Garry Ludwick. Any engine that uses points and condenser, pre electronic ignition era, knows you are right!
@@deanhenthorn1890 I have this same engine and the points are OPEN most of the time. I've seen a few engines that work like this including the Onan engines. My understanding is that either system can work to break the electrical field and cause the energy to pass through the secondary winding and through the spark plug to ground.
Thanks for the video. Good stuff and a generally clear explanation. I feel you may have got CDI and points ignition systems somewhat confused. What you may find happens is that the current generated as a double and reversed wave ( as you pointed out) is allowed to flow through the points to ground creating a circuit. This circuit is broken by the points at the peak of the second wave, The condenser does stop arcing but more than just to save the points it precipitates a sharp instantaneous collapse of the magnetic field and it is this which generates the massively high voltage in the secondary coil. Keep up the excellent work I love your tips!
My thoughts as well, until later in the video he shows a points system I haven't seen, a bit different to a motorcycle or car but yes, is points, well... a single point lol
you have an error in your explanation there is no current flowing thru the points the points open lifts a gd off the condenser lead allowing a current flow thru the primary coil thru the condenser to gd via the metal can and screw to the base of dist this flow creares ahigh voltage in sec . coil sending it to dist cao and plugs as points closecond lead is gd again stopping voltage the only time points have current is either wrong condenser or defect condenser the voltage can not get thru the cond.so it jumps the tiny gap at open points to gd which causes pitting of the points over time you can test this with your voltmeter conn to the cond lead with switch in run pos you will see batter volts (12) on that screw now open the points the voltage falls off. hope this helps some one most of the time the condenser is failing if you have spark tbls.
@@frankdavidson9675 Either you don't know what you're talking about or you need to take a writing class so you can effectively put your thoughts and ideas on paper for people to understand. I know conventional ignition systems (points and condenser) like the back of my hand and I have trouble understanding what you wrote.
Great explanation on points, ignition system!!!
I have a Wheel Horse that I bough new in 1976 that has points. Years back I pulled the flywheel only to find that the points are conveniently located on the block. Can’t beat experience or having a manual :)
Yeah, you learn from experience. I've done that to many times.
Do you really have a 'dent' in your crankshaft ? Normally there's a 'bulge', because the secondary circuit gets activated when the points open, not close as you say! Or is this only with battery equipped systems? Does this system work the other way around than normal? please clarify, some1...
This seems to show the spark plug fires every stroke but it seems a four stroke should fire every other stroke. I suppose it could fire right at tdc of the intake stroke also and it wouldn't affect anything?
Exactly it's what they call a wasted spark system. All small engines fire on the intake stroke as well as the compression.
I have a TecumsehH540 or HS40 and the points are closed all the time until a lobe on the crank open them up for a few degrees of rotation, seems backwards from what you say being open 90% of the time, either way, no spark and while points are open no resistance from the open point to ground, I haven't worked with points for 30 years so I forgot alot. Any ideas on how to test? Nice Vid!
I do have a video on swapping these th-cam.com/video/HV9MJwsUP_4/w-d-xo.html
but your already in so may not help much. The most common, no spark culprit in order is: dirty/greasy/corroded point connection that don't make a good connection, the ground kill wire still engaged, dead condensor, shorting out the spark, and finally a dead ignition coil.
So I always like to pull the kill wire off the kill location from under the carb to eliminate it. Then I run some fine sand paper(300+) through the points and spray then off with carb cleaner or brake cleaner to degrease them. Then I try to get a spark.
Thank you and Well done........I have a Puch moped........the ignition system incorporates a "kill switch" fitted to the handlebars...........wil this basically be a open circuit or a grounded circuit, to/from the coil ? Thanks
Most are just a ground from the coil to prevent the coil from building up a charge.
A day that you don't learn something is a day wasted. I have picked up a lot of information and you have jogged my memory every now and then. Thank you!
Thanks. I'm glad you enjoyed it.
Thanks for the video. I've got a little 2 hp Briggs 60102 and after it started running lean and dying on me, I decided to replace all of the gaskets (intake, gas tank, crankcase, valve cover, and even the head gasket). I had adjusted to carb with no luck, so I figured I'd just do a little overhaul since the gaskets were cheap enough. I checked the points and condenser and all seemed really clean plus no cracks on the top of the condenser. I sanded the points and set the gap to 20 thousandths, although they were pretty clean to begin with and the gap was at 22 thousandths before. I fired it back up and it will run quite well at half throttle and idle pretty good, but will sputter and want to quit at full throttle. Tried adjusting the carb both directions with no luck. I would assume my points and condenser are fine if it runs so consistently at half throttle, but thought I'd run it by you to see what you think. I just regapped the spark plug, but figure I could replace that just to eliminate it as a cause.
tlgrimmy Sounds carb related. The fuel pickup tube that drops into the tank can become blocked. It has a fine mesh screen and it can become blocked if you have a rusty gas tank. Before this I would make sure the Main Jet is clean by unscrewing the nut+screw as an assembly. Then remove the Jet with a wide flat head screwdriver. Spray carb cleaner through this. Inside the carb hole that your pulled the Jet out of there are some holes behind where this jet sat; clean those as well. Generally if the engine sparks then it sparks and doesn't change with RPM; if anything it gets stronger with speed.
sixtyfiveford Thanks for getting back to me so quickly, much appreciated! After reading your response, I pulled the needle and jet, cleaned everything up thoroughly as you mentioned and then I noticed that the needle had a bur on it that I hadn't seen before. It looked as if it had been screwed in all the way and tightened down enough to ruin the taper on the needle and create a bur. That makes sense of the issue with the needle not making much difference on gas flow, as that bur was probably restricting flow. I chucked it in my drill press and carefully filed away the bur and polished things back up. I put it all back together and viola! It runs infinitely better now. I did end up having to keep the needle out only 1 turn due to shortening it when I filed it down, but at least I found the culprit. I'll go ahead and buy a new needle and jet just to get it at it's best though. Thanks again for pointing me in the right direction, that really helped! Feels good to have the problem finally solved.
That's great. Keep in mind that it really isn't important how many turns out you go. The 1.5 turns is just a number to get the machine running but it needs to be fine tuned from there. At full throttle turn it in slightly until it begins to stumbles then out until the same occurs. Set it to the middle of these readings and maybe even 1/8+- of a turn out.
Your video was excellent, I have question about a 1975 16 hp Briggs engine as to where the magnet wire wire From the ignition switch is connected , is yellow wire or m wire hook to the points Thank you Jim
Sending a big hug to you my friend, from Argentina, once again spreading and teaching very useful information! See you!
I hate to tell ya buddy but you have it backwards….The points stay closed most of the time as the primary coil is being charged up.The moment the points open up, the primary field collapses inducing a current in the secondary winding which goes down to the spark plug firing it off. The condenser does stop the points from arcing a lot, that is true.
A few days ago I was digging int o a small 5 horse Briggs that had no spark. And the points actually do stay open most of the time and close very briefly. I'm so confused because with literally every other points I have experience it's the other way around. And I still don't know if it's supposed to be like that.
@@bestelitt2760 I have seen that too…The spark occurs when the points open…Regardless of how long they stay closed.
Even on youtube will see video's by mechanics, auto electricians and others who have absolutely no idea that the condenser (capacitor) boosts the secondary voltage. Good video.
How can the condenser send current back through the primary while there is no return path to ground. The points open, which breaks the ground. The magnetic field collapses causing current in the secondary. Once the points close again, the stored current is fed back into the primary and helps boost the next cycle. Current cannot flow without a ground or am I missing something here?
Hard to explain without a video or drawings. Some sites miss out on some details. The information you are looking for must mention the condensor absorbs the points spark but also provides the reverse direction current required to generate the high voltage. Try th-cam.com/video/W94iksaQwUo/w-d-xo.html
Thanks for the reply. I've been looking online to see how exactly this works being as there is no path to ground while the points are open. The condenser is grounded, so maybe it's just in the way the condenser is made?
I found the answer :-)
Once the field collapses in the primary winding's, the voltage stored in the condenser is higher than what's in the primary circuit. The insulated foil sheet inside the condenser forces the stored voltage back through the primary winding's, which makes for a longer duration spark at the plug. This keeps happening until all the stored voltage is used up.
I had to search a lot of old books to find this info. Finally found it in a auto fundamental's book from 1960. Thanks for the thought provoking reply :-)
Very informative thanks . I have a 1978 Bultaco Sherpa 250. Can't seem to get it to run right, it'll run at full pelt or not at all. Think I might have wired the primery ciol up wrong or may have a short some where. are the Primery and the condeser bolted to the engine ( to ground ) or are they insulated in some ay
Are you sure it's not a fuel/carburetor problem?
Good explanation of how points work..... do you have a vid on a lawn boy D series engine points setup. Thanks
A secondary tap of the coil provides a signal to do many things prior to hi voltage rectification for the spark plug. Many people are
looking for passive analog devices to support electrical needs sans onboard battery.
one month or more in school where i can leaned this things in less than 7 minutes...thanks man!
Thanks.. I'm glad you enjoyed the video.
Just a quick question the new points I installed for my Kohler K321. If I can see a bright spark when the motor is turning over would this indicate a bad condenser? Thanks for posting the video.
Amazing video! Lawn mowers, generators... a lot of different applications 👍🏽
Thanks, I'm glad you liked it.
What about magnetos for twin cylinder engines? I believe the secondary coil is not grounded by a coil tap and only grounds by arcing across both spark plugs.
Your explanation is incorrect.
Wikipedia better explains:
In the type known as a shuttle magneto, the engine rotates a coil of wire between the poles of a magnet. In the inductor magneto, the magnet is rotated and the coil remains stationary.
As the magnet moves with respect to the coil, the magnetic flux linkage of the coil changes. This induces an EMF in the coil, which in turn causes a current to flow. One or more times per revolution, just as the magnet pole moves away from the coil and the magnetic flux begins to decrease, a cam opens the contact breaker and interrupts the current. This causes the electromagnetic field in the primary coil to collapse rapidly. As the field collapses rapidly there is a large voltage induced (as described by Faraday's Law) across the primary coil.
As the points begin to open, point spacing is initially such that the voltage across the primary coil would arc across the points. A capacitor is placed across the points which absorbs the energy stored in the leakage inductance of the primary coil, and slows the rise time of the primary winding voltage to allow the points to open fully.[5] The capacitor's function is similar to that of a snubber as found in a flyback converter.
A second coil, with many more turns than the primary, is wound on the same iron core to form an electrical transformer. The ratio of turns in the secondary winding to the number of turns in the primary winding, is called the turns ratio. Voltage across the primary coil results in a proportional voltage being induced across the secondary winding of the coil. The turns ratio between the primary and secondary coil is selected so that the voltage across the secondary reaches a very high value, enough to arc across the gap of the spark plug. As the voltage of the primary winding rises to several hundred volts,[5][6] the voltage on the secondary winding rises to several tens of thousands of volts, since the secondary winding typically has 100 times as many turns as the primary winding.[5]
The capacitor and the coil together form a resonant circuit which allows the energy to oscillate from the capacitor to the coil and back again. Due to the inevitable losses in the system, this oscillation decays fairly rapidly. This dissipates the energy that was stored in the condenser in time for the next closure of the points, leaving the condenser discharged and ready to repeat the cycle.
On more advanced magnetos the cam ring can be rotated by an external linkage to alter the ignition timing.
In a modern installation, the magneto only has a single low tension winding which is connected to an external ignition coil which not only has a low tension winding, but also a secondary winding of many thousands of turns to deliver the high voltage required for the spark plug(s). Such a system is known as an "energy transfer" ignition system. Initially this was done because it was easier to provide good insulation for the secondary winding of an external coil than it was in a coil buried in the construction of the magneto (early magnetos had the coil assembly externally to the rotating parts to make them easier to insulate-at the expense of efficiency). In more modern times, insulation materials have improved to the point where constructing self-contained magnetos is relatively easy, but energy transfer systems are still used where the ultimate in reliability is required such as in aviation engines.
Edit
so when that gap is closed and points are touching eachothers then it will give spark?
Great video! How do you figure out if a condenser is still any good?
You can use a capacitance tester to test the mfd. However most people don't have one of those so, in that case it's easiest to just replace the condenser if it is over 10years old(though I have seen them go 40+ years without issue)
@@sixtyfiveford hmmmm. I have a mcculloch eager beaver top handle chainsaw.. spark isn’t the greatest so it doesn’t start. I’m thinking it’s due to the condenser/capacitor. My multimeter read 1 microfarad but I’m not sure if it’s within spec as the capacitor doesn’t have any labeling on it.. I did read online that most chainsaw capacitors read .22mfd. If that info is correct, mine is wayyyyy out of spec! Would getting a condenser designed for cars and similar in size work? Trying to avoid paying the $30 for an old brand name McCulloch condenser when I can just pay a few bucks for a generic brand from the auto parts store..
@@berniemac8413 I have swapped condensers many times. Most of the time I use the cheapest Briggs and Stratton ones but they might not fit into a chainsaw. But have never had an issue swapping them around.
@@sixtyfiveford thank you for your input! I will look for lawn mower ones!
Come On Let's help this guy get to a thousand subscriptions!
What should be the distance between the fly wheel and the transformer? Should it be a couple a thousand or touching it? Thank you. Good explanation.
.020"gap is standard.
Thank you
Thickness of a business card will do...
I already knew all of this but I guess your so captivating I had to keep watching LOL This is Awesome for a new beginner in small engine repair.
Yeah, not many points machines left out there but it always helps to know how stuff works.
I have a Wisconsin Engine on a Essick Plaster mixer, I was told once a magneto gets wet it ruins it. I wish you could show the points or magneto. Q. Is the transformer & Magneto the same?
Time to go back to school. The points stay CLOSED most of the time. When the points OPEN momentarily, The field collapses at that point, and the magic happens. Careful what you tell folks.
We should just leave it as "It's magic" instead of people trying to explain the magic "as they understand it"...besides this is old magic that most people will never witness as we have new magic nowadays.
I agree with you.Closed
most of the time
If the contacts close every rotation of the crank, does that mean the spark fires on both the Intake and Combustion cycle?
mon0railbredpig Yes.
mon0railbredpig Yes the plug fires every intake/compression cycle and exhaust cycle but this has no ill effect, in fact it has no effect during the exhaust because there is nothing to burn.
i'vу been looking for this video for sooooooo long. thank you kindly
I'm glad you liked it.
do you know approximate resistance of the coil of an 8hp Tecumseh thats in a snapper rear eng mower?
The hardest part is resisting the urge to throw that piece of shit in the garbage and going and getting yourself a good old reliable Briggs.
Do you know about villiers C45 industrial 4 stroke engines and magnetos timings.
I like the good clear explanation and demonstration
Thanks, I'm glad you liked it.
Great explanation! Thanks!
In order to obtain a very HIGH VOLTAGE in the secondary, we need a GREAT FLUX CHANGE through the core (implicitly secondary coil), because the greater the flux change the greater the voltage obtained. Therefore, besides collapsing the flux in the primary, we ALSO REVERSE the current direction through it, obtaining a GREATER FLUX DECAY through the primary, and this is exactly what the capacitor does. A capacitor always opposes a build up in voltage by charging itself. The contactor circuit here shortens both the primary coil and the capacitor. The capacitor opposes the build up of the induced voltage in the primary by charging up, and immediately after the circuit opens (10 degrees after Neutral, EGAP), the capacitor is no longer shortened by the contactor, so it discharges solely through the primary coil.
Keep in mind, that any collapsing magnetic field through a coil, give rise to a self induced current through that coil. In our case, the self induced current due to the collapsing magnetic field is opposed by the capacitor current through the primary, thus hurrying up the collapse (according to the Right-Hand Corkscrew Rule) !
In other words, the capacitor only forces a reversed current through the primary, to oppose the selfinduced one, in the end accelerating the collapse of the induced magnetic field. This happens very quickly, right after 10 degrees past Neutral (EGAP).
At this point, the CHANGE of the rotor magnetic field in the core is just below peak value, which means the EMFs generated in both the primary and secondary coils are just below maximum. Also, the CHANGES in the rotor magnetic field and the collapsing primary field have the same directions (very important)! As the two magnetic fields have the same direction of change, they will superimpose, thus give rise to a LARGE FLUX CHANGE through the core, implicitly through the secondary coil. This is like a spike in the magnetic flux change through it, leading to a very high EMF at the ends of the secondary, which translates in a spark obtained at the sparkplug.
Moreover the capacitor and primary coil form a tuned LC circuit.
All this starts when the EGAP commences and up to the point when N reaches the yoke (Full Register position), the superimposed flux change being large enough to create the spark.
th-cam.com/video/OMLSNwQiiKg/w-d-xo.html
I had a ST350 Ariens snow blower with no spark so I change the Ignition coil- condenser and the point but still no spark
can you help me
thank you
Make sure the kill wire isn't engaged. This can be with a key switch or throttle set to low. It's probably best just to disconnect it from under the carburetor and let it dangle out of the way.
I've seen points and condenser's but never really knew how they worked, interesting stuff. Very informative video.
Thanks for watching.
i fitted a stihl points type ignition plate in an old echo saw... got NO SPARK until turning in wrong direction and then big blue spark.....checked position of strongest magnet and cut a keyway to get magnet leaving 2nd armature end as points open.... now sparks but weaker. strange as the stihl was anticlockwise rotation and echo is anticlockwise rotation....
I've swapped non-points Echo trimmer coil into a old points Poulan saw and it fired right up and I use it still. I know that the position of the magnets can be either North inwards/South outwards or South inwards/North outwards. If the coil is setup to pull off of North and it is in the inward position, it is like having a 3/4in flywheel to coil gap, which will give a weak spark. Briggs and Stratton had issues when they went from points to breakerless and flipped the polarity of the magnets in the flywheel. Customers were so mad they offered to repolarize the flywheel for free so people could put breakerless coils on their points machines. Later they switched back to the standard they were using before.
Really appreciate this information. I have a Tecumseh H50 that I'm trying to get running and couldn't wrap my head around how the ignition worked. Thank you!
+Bike Man Dan You're welcome. I'm glad it helped. I do have a video on the Tecumseh points system th-cam.com/video/HV9MJwsUP_4/w-d-xo.html
I just bought a used Toro groundmaster 52(1979) it was running well and cut beautifully. It died while I had been cutting for about 1.5. It will turn over, but no spark. Have changed the armature, did as instructed on your video re condenser and point, checked to see if any wires in harness broken extra, but still no consistant spark, only once in a blue moon. Any ideas. Seat kill switch as been bypassed.. thxs
conwald1 This is the point system you have th-cam.com/video/QQqhvA5qo2c/w-d-xo.html . You can pull the kill wire all together to make sure it's not grounding out.
sixtyfiveford Mine is screwed, if you take off the kill swich, it will not turn over.. hook it back up, it will turn over. So something is wired backwards. Trying to find a new points and condensor, having a hard time. Looking at maybe the solonoid.
The points and condensor are easily obtainable from hundreds of online places. Don't search for them under Toro as they have nothing to due with Briggs and Stratton. The wire going from the coil to the points needs to stay in order to run, but the wire running from the points the tractor can be pulled off to test(kill wire). If you're getting intermittent spark more than likely you just need to sand the points with a very fine sand paper.
sixtyfiveford this is the problem, its backwards on our tractor. When we disconnect the wire from the points to the tractor it will not run. It will not even turn over, its absolutely dead. Connect it again and it cranks. Go figure. We are totally baffled.
Let me explain a little more clearly as I may have misdirected you a little. There are 2 wires coming from under the flywheel going to the coil. One goes to the points and the other comes out and is next to this wire but never touches the points. This is your kill wire and will go up into the loom to the ignition switch and all your safety kill wires touch this single wire. This is the only way the ignition is shorted out. You can simply unplug or temporarily cut this wire to eliminate the possibility the safety switches on the mower aren't killing it.
It is possible to remove the magnetron and put on the ignition system of a motorcycle.
Thanks for sharing this video! So if I'm seeing a bright spark at the points when my Koler K321 is turning over should I assume the condenser is bad?
+Farmitecture Yes, if you're getting no spark at the plug. A few random sparks at the points is normal but not all the time.
+sixtyfiveford Thanks for your quick response! I am getting spark at the plug and a constant spark at the points. The motor does start but won't stay running at low idle unless I open the points all the way but then it won't keep running at fast idle it skips and misses and eventually stalls. When I set the points to max (they are only supposed to be .020 for this K321) I get a brighter spark both at the points and the plug maybe that's why it stays running then? Any thoughts?
Personally it sounds more like carb problems. A weak ignition system will falter at high rpms but generally works fine at idle.
I have rebuilt the carb and adjusted it to the manual and them some to try and keep it running when I set the points to .020. If I set the points to full open It idles great at low rpm but won't run smooth at high rpms. Thank you for you thoughts!
If the carb is good, you're on the right track with the condensor.
oh thank you so much i have my test and i needed an explanation about Condensor
Good video gets right to the point.
:)
I have to ask I have a vintage dirt bike and I just replaced the points and condenser and it's still sparking at the points when not running so do you know what the issue is?
Thanks
+Simon De Asian Sounds like a bad condenser.
+sixtyfiveford
I checked that and changed the condenser and points so I'm not sure the book says it should read 5.9 ohms at the coil (spark plug) but I'm reading 10.25 ohms I'm not sure if they add up or not
+sixtyfiveford does this mean including the boot for the spark plug? The boot reads 4.9ohms and the end of the coil (no boot) I got 5.2(something)
The condensor is responsible for stopping the points from sparking. I'm assuming you old one was toast?
Thanks for the excellent video! ...two questions:
1) Is the spark plug mounted above the EXACT center of the piston on top of a combustion chamber.
2) Also, at TDC, how far from the piston is the bottom of the plug?
This information will be of GREAT help!
Thanks much,
1) No.
2) varies by engine.
the plug can be any where in the head as long as it not touching any thing look at it this way on compresion stroke you can light it with a spark any where
Great simple overview and explanation. I can and have done mechanical repairs but the electronic parts have always been a bit of mystery to me..........Thanks again.
Thanks. I appreciate your feedback.
That is the info I needed. Thank you!
Hey, great video. I'm struggling with an old Briggs 2hp... I'm getting power to the plug but not enough to make it jump. Any ideas?
Weak spark would generally be a bad condensor. But you say you're getting no spark so I would clean the point contacts.
@@sixtyfiveford sorted, thanks!
I have a small engine with this, and I get power to the top of the plug, but no spark. I put the plug in another engine and it has spark. I cleaned the points and the coil seems to be working (idk how he tested it). What would anybody suggest?
Too wonderful in your detailing. But I am still having difficulty of no spark in a very old Kohler engine Cleaned the points but still no spark not sure of condenser but as you say they rarely go. I must still have a bad condenser.
The condensers do go bad, just not as often as the point contacts. If a quick clean of the points doesn't restore points, I generally put a new condenser in.
Check to make sure the wire between the primary and the condenser is not shorted out against the engine block.
Sometimes if the wire accidently touches the hot engine block, the insulation melts and causes a short circuit that prevents the coil from charging the condenser.
Found this out the other day when replacing a condenser on an old Montgomery Ward generator.
Hi, good explanation. You need to follow up on how the engine revs are governed as well as the theory behind the engine revving up and down. Thanks
I'm on top of it. Right here th-cam.com/video/bOHv3X42-wk/w-d-xo.html
An engine that revs up and down is a clogged idle circuit in the carb.
Thanks
Great vid... Would love to see if you come across points failing in leaf blowers. I've had two blowers go bad (no spark) in 2 years. The latest was a Poulan. Noticing on youtube a lot of the poulan leaf blowers are failing for different reasons.
+averagejew Only stuff made pre mid 80's will have points. Other than that your ignition coil can short out but it is pretty rare.
Hi great video. Wondering if anyone can help me. Kohler 8hp K181
. Replaced coil, still no spark. I am thinking I probably should have ordered a condenser also. By the way only way for me to find parts is EBay, straight from China of course so just hoping they are good. Anyway in Checking the condenser, I am on 20k ohm setting, Red probe to wire, black too body, meter just stays at 1, should I not see a certain ohm reading, meaning I am charging the condenser? Also I would then check dc volts I believe, what am I looking for MV of something , then voltage should drop? Thanks for any help.
The condensor needs to be disconnected to test and should read around 30mfd from the body to the nipple. The coil is very very rarely the issue in lack of spark instances and generally dirty points, followed by failed condensor are the issue.
sixtyfiveford hey thanks so much for getting back to me. In my case a new coil fixed my no spark, but back to my original problem I had before loosing spark. For a couple years now I have been having the same thing. Runs great for anywhere from 15min to an hour then starts running rough. Let it cool and starts the same process. I just put on a spark tester and spark looks intermittent when running rough. I took a video but not sure if I can attach it. Could that be a condenser? I have ordered one don’t have it yet.
@@rltkktlr Absolutely I would replace the condensor. It is a wear item and over time won't hold the spark energy needed to collapse the field and create a spark.
sixtyfiveford thanks, I should have ordered one with coil. Will let you know the outcome. Great channel by the way
sixtyfiveford ok got the parts, points and condenser, replace condenser, I certainly would have replaced the points but got lazy, it’s on a walk(push hard) behind leaf blower and blower would have had to come off get to points. Maybe a 1 inch screwdriver which I don’t have. So anyway condenser didn’t fix it so I threw in the towel bought a electronic conversion chip, $30, very easy to install, no more points and condenser, and great spark and runs great. Thanks again, great channel you have.
Don’t need North and south poles on flywheel only one polarity. When the magnet passes the magnetic field collapses and induces a voltage to secondary weather AC or DC it’s the same. Grounding the primary should not cause the spark to open, if so please explain the path for current.
Btw, every magnet has a N and S pole, every magnet...it's the nature of the physics! Lol
what r symptoms of weak spark I have a old Neptune Outboard it don't wanna jump the spark across the spark pulg but when I hold the spark plug wire with my hand to ground I get a shock
More than likely the point contacts are dirty or the condensor is weak/dead.
sixtyfiveford I cleaned the points so it probably the condenser like u said ima just replace them both thank for the tips an reply grate video by the way
Excellent explanation - I’m confused at how grounding the primary circuit stops production magnetism since the fly wheel is still spinning wouldn’t the voltage still be induced into the primary? Current would flow from the grounded primary to the other side of the primary completing a circuit. I know clearly I’m wrong I just don’t understand.
I want to add, I don’t think the magnets on the fly wheel need to have both positive and negative polarities, if we look at a coil pack on modern engines they use the 12VDC from the battery to operate. All we need is a magnetic spinning on the flywheel to cut flux into the primary coil.
Grounding the secondary makes perfect sense to shunt the spark back to the coil but also raises another question - when doing so wouldn’t the current from shorting to ground be high due to the voltage being extremely high? I would think the secondary’s coil would short out.
if primary coil is gd. there is no current flow even tho wheel is spinning you can not have voltage and gd at the same time
have outboard motor. won't start. if condenser is gone will I still get any bit of spark
If the condensor is bad, you shouldn't get any spark.
+sixtyfiveford . I have an suzuki dt 7.5 outboard motor. I've loads of petrol and compression and some spark. I've put new points and reed valves and two new original plugs. still won't start. any ideas.
You should be able to run a spark test and get the spark to jump a 1/4" gap. This will ensure a strong enough spark to run. 2 strokes are easily flooded with too much fuel, to clear the fuel, pull it over a few dozen times with the plugs removed(choke off full throttle).
Awesome...thanks for the info. Hope your having a good winter in Salt Lake. Its been a banner year for plowing and pond hockey here in Cleveland.
It's been really mild. I really enjoy a ton of snow so I'm envious.
Great video, very useful, thankyou.
nice video I just start working on small engines I pick a 12 hp Tecumseh with points in the side of the block and condenser beside the coil and am just getting really weak spark because somebody pull all the wire from the points will appreciate some help
Weak spark will either be dirty points or possibly a failing condenser.
thanks I think condense is bad
The primary collapses. The secondary does not collapse. When the primary collapses, a high voltage is induced in the secondary, and this induced high voltage is what creates the spark.
Very complicated. How did anyone think of points and condensers?
A fountain of knowledge - thanks!!
Thanks for watching.
Hello, I was very pleased with your explanation on how dynamo ignition works, didn't have a clue until viewing your videao. Maybe a stupid question but I'm wondering, how high should the secondary voltage (feeding the spark plug) be? Would that be like hundreds- or thousands of volts? Up until now, haven't risked to test it.... maybe for the best..... Kind regards, Jacques Belgium. So as you can see you've got viewers all over the world although Belgium is a small European Country.
I would guess it to be around 10,000-20,000 volts.
Hey....I love your comment and maybe you could explain 8 HP Begium Horses vs 8 HP Harbor Freight engines.
Thanks for this :) been working on making a Honda CG125 run off it's own steam with no lights or main loom or anything as a fun little flat tracker project and whilst I kinda knew what to do, I've never had a points bike before so this confirmed everything for me :)
I hope you get it up and going.
Nice, simple explanation.
Thanks Flak.
This is some pretty fascinating information
Thanks.
Hello sixtyfiveford@@@ I was wondering if you can help me with my problem I have a ruggerini small engine that it's working but the condenser it's about to run out due to the wire it's coming a parts from it, I was wondering if all the condensers works the same because I just can't find the condenser for this engine please help
I've swapped condensors from other engines and they all seam to work the same. I've picked ones that are virtually the same size.
sixtyfiveford thanks alot for sharing this with me I was just wondering because I have one new setting there so it's the one should be doing the job next
Like the simple explanation
Good tutorial and a very simple explanation. Even I could understand it. Thank you.
Thanks.
Hey man, I have been wondering for a while now how to sort the mystery of this system as I bought a 1978 Honda CB550k. This really clarified it, and I'm sure I'll watch it a few times. Thanks!!
I'm glad it was helpful.
Very interesting, never know that. Neat and clear explanation.
Thank You.
A-4 cycle engine needs a spark every other revolution. It looks like this will provide a spark each revolution like a 2-cycle engine. How do we account for this?
They call it a waste spark system and it is on virtually every small engine. It simply sparks on the exhaust stroke and does nothing.
Can it be done if the coil is on the inside of the flywheel. I haven't been able to find a Vid. that covers my problem. The coil is on the inside of the wheel
Sehr Gut!!! great teaching video -- I could Not have done any better!!!
Danke. I'm glad you liked it.
NEXT lets do How a inductive (HEI) type of IGNITION CIrcuit functions????
Magic.. :)
Thanks for helping me understand watt going on. I do like to know watt happens. It's all good stuff.
Thanks.
its not watt thats amp times volts its what
Aren't some small engines ie Briggs Stratton 12.5 Hp I/C Vert shaft pointless and condenserless ?
Yes, since 1984 all Briggs are point and condensor free.
So what is the mechanism to insure the exact microsecond of spark without points (now that I think about it); is it the more exact manufacturing so they know exactly when that mag field will collapse creating the surge of current in the primary thus secondary coil to spk plug? FYI: Model T's & i think A's had a separate coil for each cyl? so that if the key was on, the coil on tap would just sit there and keep sparking indefinitely . I found a condenser believe it or not from the old days "60's"
I'm a female and I love this stuff!!.....
;D
I have a 5hp tecmsh that starts inconsistently.......I cleaned the carb and replaced o rings, etc......but am still having probs......my next task is to check the points, condenser and coil.....
THANX!!
sbecktacular Awesome. The coil will either work or it won't but the points/condenser can be intermittent. I'm sure you saw I have a video on them th-cam.com/video/HV9MJwsUP_4/w-d-xo.html
hey thanx!...
turns out my motor doesn't have points it has the magnetron? coil......I did alittle fiddlin' with it this morning and it's running GREAT!
thankyou for all your informative vidz....much appreciated!
Awesome. Great work.
All i know is the amount of times my vintage brings and stratton flathead that doesn't have a spark plug boot has shocked me lol.
That'll keep you on your toes.
@@sixtyfiveford well also because I built a see through engine out of it like warped perception did and I used a screw in place of the spark plug where the spark jumps from the tip of the screw to the engine block in the combustion chamber between the valves and piston so a lot of exposed metal.
My spark advance module plugs to the second prong
seems to be some confusion about points ---with points closed nothing is happening every thing is grounded when they open it removes the ground so current flows thru cond. to ground that flow going thru coil creates high voltage due to turns ratio of windings causing spark
another great info vid bro, cheers
Thanks.
very nicely explained
Thanks.
When the points are closed and the electricity is "flowing out" Where does it go? Just to ground?
to the spark plug
Thanks for the video, good info.
Thanks.
no, sorry, direct current, the + end of the magnet drags the e- in one direction, and the - end pushes the e- as IT passes by. capacitors can ONLY STORE DC. But you were close.
Great Demo !!!
Thanks.
65!! I love your banner!! Excellent explanation of how the entire ignition system works on a magneto engine!! Where did you get your banner made? Cheers!! Zip~
ZippoVarga Thanks. I got it made online. It was at a party store shindigz.com. Create-A-Banner 18"x54"
Great video as always SixtyFive!
Thanks. Glad you stopped by.
Nice info :) you do a great course in misc great stuff to know if you like to fix and work on stuff. ... you can use that if you wanna lol. I've got a Walmart Mower that's been great, but it's totally different than anything I ever saw, baffling a bit, but I better figure it out cause grass will be coming soon.
Yeah, once the grass starts growing it won't stop.
Your close but mostly wrong. At the precise moment the points open (not close) the ground is broken which causes the field in the coil to collapse and go to ground through the spark plug. The purpose of the condenser in layman’s terms is to protect the points by absorbing-the excess spark that would jump the points to ground and weld them when the field collapses. Nice video.
Armature is actually the core of the coil.
Smashing video :-))
Hmm i allways thought the capacitor and primary were like a tuned circuit and produced a stable magnetic field, then when the points closed the sudden loss made the primary over react (as charged inductors dont like change) and create a spike of intense magnitism trying to counteract the loss and firing the secondary.
Looks like i may have been wrong :-((
Inductors do react to losses though, they do have some very odd propertys lol.
I knew the basics but I had to read up just to make sure my ideas were right.
This information is excellent.
+Thetrucky69 Hey Thanks.
Not a problem at all champ. Very accurate info, cheers.
Thanks for explaining this.
Thanks, I'm glad you liked it.
Thanks. Very helpful.
Glad it was helpful!
When did they stop using points and condensers on small engines?
Small engine manufactures stopped using them around 1983.