Test Any Ignition Coil With A Multimeter! (Easy DIY Tutorial!)

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  • เผยแพร่เมื่อ 24 ธ.ค. 2024

ความคิดเห็น • 273

  • @VintageEngineRepairs
    @VintageEngineRepairs  ปีที่แล้ว +35

    If this video helped you, please consider clicking on the THANKS button above to support my channel 🙌

    • @fredwilliamsonmiller7214
      @fredwilliamsonmiller7214 ปีที่แล้ว +2

      Hey Tom, thank you for your work on these small engines, enjoy your delivery. Watched one of yours on carbs( I think?) recently. I am struggling with a leaf blower at the moment but also have a trimmer, a chainsaw, a snowblower and 2 mowers. All of these little engines run great for years but the 2 stroke ones seem to eventually get into more issues. The2 stroke blower has been shifting from issue to issue, surging (solved by carb rebuild), wierd running (partially solved by filing the new metering diaphragm tip to close to original ~0.60", came in at double that), starting and running issues especially when hot - partially solved by adjusting the carb screws, now every indication of no spark. Plugs new and old tested at 2 ohms each - ok, plug wet when trying to start( no spark?), kill wires and ignition permit switch test ok, new fuel, rebuilt carb, new fuel filter, air filter ok, etc, etc . Pulled the module and used your testing theme with my trusty Multimeter......secondary - plug wire to armature = 4.2Kohms.....slightly low but ok(?); primary - armature to kill tab = 148Kohms, plug wire to kill tab = 158Kohms. I assume the electronic stuff is hiding the 0.5 to 2.5 ohms of the primary. Awaiting delivery of a new module. Can not wait to test it. Any thoughts on the ~150Kohms readings? Keep up the excellent work, learning at Warp 9. Thanks Fred

    • @darcymunro8930
      @darcymunro8930 9 หลายเดือนก่อน

      I like the bottle brush tree in the background.

    • @KaganEatsPussy
      @KaganEatsPussy 9 หลายเดือนก่อน

      are these numbers the same with a 6 volt and a 12 volt coil?

  • @gerrydepp8164
    @gerrydepp8164 ปีที่แล้ว +54

    I had my own workshop for 30 years and murphy was a constant companion so more often than not there was more than 1 problem or inconclusive. If I had a buck for every coil I tested that had good values but was crap....in the end I gave up these tests, it is only an indication ie if the coil is crap this will confirm it...or not. The most useful test (and fast) if the motor is running - but has an ignition problem - is to remove the cap from the coil and start the motor while holding (and being very careful) the end of the lead to the plug or earth if you have more than one cyl. The spark should be fat strong and blue and most importantly should easily be able to jump about 6mm. As you are holding the lead you can easily vary the distance and if the spark faulters and or the engine stops as soon as you increase the distance the slightest from the plug you know that either the coil is faulty or there is not enough power (dodgy electronics normaly wont let the engine run at all) - you have to then eliminate the plug first too of course but most often it is the coil. But if the spark and engine is still going strong with sparks an inch long you know the coil is not at fault. The next test is then the magneto coil (or with a battery ignition simply to measure the voltage at the coil - this will be pulsed if the electronics are not in the coil). Also here there is little point in measuring the resistance thru it as what makes these tests so inconclusive is a broken down insulation not bad enough to open or short it but just enough to allow moisture to get in. This then shorts it as soon as voltage builds up - same goes for the ignition coil. So you need a peak voltage meter which can be bought cheap and put in series on your multimeter. This then allows the multimeter to accurately measure the very short voltage spikes put out by the magneto and immediately shows up any problems with power supply as a high enough voltage of about 90 - 200v AC will not build up. You need to confirm those values depending on what bike/other you have as that is just from memory and I am retired now! There are also measuring charts for assessing the electronic parts but they can be hard to get right as they will vary depending on which multimeter you have. Sometimes all you can do to verify those is to employ a process of elimination. The best part of this vid was how he eliminated the TCI part of the coil from the test - well done. Hope this helps someone! All the best from Aotearoa

    • @VintageEngineRepairs
      @VintageEngineRepairs  ปีที่แล้ว

      Thanks for watching and sharing 👍👍

    • @emanuelmifsud6754
      @emanuelmifsud6754 10 หลายเดือนก่อน +2

      Excellent comments especially about the blue 6mm long spark jumping from plug to earth. You are absolutely correct. Manufacturers tell us about blue thick spark.
      Video author forgot air gap. If rust present it shorts magneto results in no spark. A failing plug sparks orange

    • @VintageEngineRepairs
      @VintageEngineRepairs  10 หลายเดือนก่อน +1

      @emanuelmifsud6754 Hey! Thanks for watching :) Though rust doesn’t affect the magnetism, it will affect the air gap clearance.

    • @emanuelmifsud6754
      @emanuelmifsud6754 10 หลายเดือนก่อน +2

      @@VintageEngineRepairs The air gap clearance is a very precise measure. Any variation to the recommended would result in the spark being deteriorated. It is essential to ensure the surfaces have no rust or loose rust. I have repaired these engines for 50years.

    • @VintageEngineRepairs
      @VintageEngineRepairs  10 หลายเดือนก่อน +3

      @emanuelmifsud6754 hi, the air gap doesn’t need to be overly precise, most people use business cards to set the gap, although I don’t, I use a a specifically made gauge. You have to be quite a way off to lose spark in my experience.

  • @TheLawnmowerLady
    @TheLawnmowerLady ปีที่แล้ว +6

    Nice video Tom! Lots of great info. I need to watch this again.

  • @mp4338
    @mp4338 ปีที่แล้ว +1

    Can you add and electronic diagram of the coil spark plug the see all the components? Maybe there is a darlington transistor inside of the coil. Who power the darligton transistor base?

    • @VintageEngineRepairs
      @VintageEngineRepairs  ปีที่แล้ว +1

      Hey; every coil is different and will have different circuitry. Best is to google the specific make and model of coil and see if you can get a cutaway or a schematic for it.

  • @clivebeswick7082
    @clivebeswick7082 10 หลายเดือนก่อน +4

    Finally someone who knows what they are talking about !

    • @VintageEngineRepairs
      @VintageEngineRepairs  10 หลายเดือนก่อน

      Thanks for the kind words, glad you enjoyed it!

  • @Jay_Ira
    @Jay_Ira ปีที่แล้ว +5

    Thanks bud. This video is timed well because I've got a saw I believe has ignition issues. This is a big help. May God bless you and keep you.

    • @VintageEngineRepairs
      @VintageEngineRepairs  ปีที่แล้ว

      That’s awesome, best of luck fixing your issue :)

    • @frankartieta4887
      @frankartieta4887 10 หลายเดือนก่อน

      A ignition issue could be as simple as a switch !
      Some things you can not see completely through !
      Faulty switches no doubt lead to the demise of barrels full of ignition coils and even whole machines !

  • @grahamjones4294
    @grahamjones4294 ปีที่แล้ว

    Thanks

    • @VintageEngineRepairs
      @VintageEngineRepairs  ปีที่แล้ว

      Thank you for the super thanks Graham! Your support for the channel It’s really appreciated, I’m glad you enjoyed the video! :)

  • @josem.2909
    @josem.2909 ปีที่แล้ว

    7:11 Pleas, Help me out here, ok so if you get inconsistent reading o the primary coil then proceed to a more accurate testing, which is testing the secondary winding:
    HT lead to armature
    HT lead to kill tab
    When you said if the reading between the HT and armature are correct, but the reading between the HT and kill tab are incorrect that means the electronic components inside the coil are bad? Or just interfering and causing higher/different reading thus giving a false sign that the coil is bad?
    So the most trusty test is between HT lead to amature?
    Or both reading HT lead to armature and HT lead to kill tab have to be the same to finally say the coil is good?

    • @VintageEngineRepairs
      @VintageEngineRepairs  ปีที่แล้ว

      Just interfering with your resistance. Secondary should always be between armature / ground and Ht, rather than the kill tab and Ht.

  • @805ROADKING
    @805ROADKING ปีที่แล้ว +1

    Well done Mate!!☻

  • @jcondon1
    @jcondon1 ปีที่แล้ว

    Great video.

  • @Nekon14
    @Nekon14 หลายเดือนก่อน

    I know this video might be old, but I’m hoping to get an answer if possible. I just ran this test on a coil out of a snowblower and I’ve got the 1 ohms across the blade and the armature so that tested well. When I go from the armature to the end of the spark plug wire I get 10. It’s a four stroke engine and you said that should be around five so does that mean that this coil is bad? It will Faintly light, my in-line tester, but will not spark the spark plug.

    • @VintageEngineRepairs
      @VintageEngineRepairs  หลายเดือนก่อน

      Hmm I wouldn’t say so, no. 10 k-oms is still perfectly acceptable even if it fits outside the typical norms we see.

    • @Nekon14
      @Nekon14 หลายเดือนก่อน

      @ ok thanks, still not sure why I can’t get spark on the engine then. The only thing that is plugged in on the coil is plug. We have a plug that is known to be good and have tried a second one also. I have also cleaned the flywheel and tried a .014 and .012 gap and the still the plug won’t spark.

  • @horserider9578
    @horserider9578 11 หลายเดือนก่อน +3

    Probably the most informative and well explained i seen.

  • @alexsmith7696
    @alexsmith7696 7 หลายเดือนก่อน

    Thanks

    • @VintageEngineRepairs
      @VintageEngineRepairs  7 หลายเดือนก่อน

      Thank you for the super thanks! Always very appreciated ☺️

  • @paredding
    @paredding 6 หลายเดือนก่อน

    V clear and concise. Sorry to be dim but ref to Kill Switch or Tab I assume you are referring to the 12v feed from the Ignition Switch. Your comment re removing all corrosion off the mounting plate is v useful as I have taken the coil off my Quattro and treated the base plate with KuRust to neutralise the surface rust that was on it. Before all this the car fired now there is nothing coming from the main HT lead to distributor BUT I have a 12v feed from the ignition switch. Could this KuRust treatment be stopping the earth getting back to the car body? Thanks

    • @VintageEngineRepairs
      @VintageEngineRepairs  6 หลายเดือนก่อน +1

      Yes, certainly scuff the surface once you’ve given it the rust treatment, there is often a layer of oxidation or surface contamination. Scotch brite it :)

    • @paredding
      @paredding 6 หลายเดือนก่อน

      @@VintageEngineRepairs OK - Thanks for the v fast reply - appreciated

    • @paredding
      @paredding 6 หลายเดือนก่อน

      @@VintageEngineRepairs I just did the test on my Martindale AM5 Analog MM: Primary on Rx 10 scale shows 1 ie 10 Ohms. Secondary on Rx 1K scale shows 7,5 or 7500 Ohms. I am now trying to find the specification for the coil (resistance)

  • @garybray3614
    @garybray3614 ปีที่แล้ว

    What is the bush/tree/plant behind you? I would like to get one if it would grow in my area. Thank you.

    • @VintageEngineRepairs
      @VintageEngineRepairs  ปีที่แล้ว

      I believe it’s called a bottle brush, as for it’s Latin name I don’t know I’m afraid!

  • @Killian665
    @Killian665 ปีที่แล้ว

    Well how do I know if the primary winding is bad or its internal electronics then if a high resistance could mean either is the case?

    • @VintageEngineRepairs
      @VintageEngineRepairs  ปีที่แล้ว

      I mention it in the video, using both the hot side tab and the armature to check secondary. One will give high the other will give normal readings. If this is the case then it’s likely just the electronics.

  • @rustybarry3405
    @rustybarry3405 6 หลายเดือนก่อน

    I'm working on a sv720-3045 kohler. I have no crank over at all. New battery, checked the starter, which tested ok. Checked plugs, they are shot. Tested coils 1 was (P) .698, (S) 17.80, the other was (P) .734 (S) 19.85. So if I understand correctly the secondary winding on both are a bit low, correct?

    • @VintageEngineRepairs
      @VintageEngineRepairs  6 หลายเดือนก่อน

      I’m not sure what range you’re working in there it’s just a bunch of numbers you’ve shared. Double check your service manual for the range 👍

  • @alexsmith7696
    @alexsmith7696 7 หลายเดือนก่อน

    Hi. I’m struggling to be confident about which are the right testing points. I know which one the spark plug lead is. I have two cables connected other than the spark plug lead. One is green and one is black. Not sure which is the kill switch lead. Can you help identify the right connection points for testing?
    I’m testing a coil for a 2022 Honda CRF 250R motocross bike.

    • @VintageEngineRepairs
      @VintageEngineRepairs  7 หลายเดือนก่อน

      I’d suggest downloading or getting a paper copy of a workshop manual, they’ll tell you step by step the process and readings :)

    • @EddieEducation
      @EddieEducation 4 หลายเดือนก่อน

      Great video Tom, as ever. Out of interest, what should the resistance be between the kill tab and the HT barb? Would it be the same as either kill to armature, or barb to armature? Thanks

  • @Daakist
    @Daakist 5 หลายเดือนก่อน

    I got a 0.37 resistance reading for the primary and 73 resistance reading on the secondary. This is a 2 stroke engine. Seems like the primary is higher than you suggested. Is it bad?

    • @VintageEngineRepairs
      @VintageEngineRepairs  5 หลายเดือนก่อน

      Hmm 0.37 ohms? If so then that’s perfect! 73 ohms on secondary? That is an issue.

    • @Daakist
      @Daakist 5 หลายเดือนก่อน

      @@VintageEngineRepairs ya 73 and im seeing no spark when turn the motor. so the 73 means 73,000 when it should be 10000 or less? okay thanks

  • @JoanneZorola
    @JoanneZorola ปีที่แล้ว

    My 2003 Honda XR400R service manual doesn't use resistance testing anymore. Instead Peak Voltage specs are listed which means you need an adapter for the multimeter.

  • @regionvoices5228
    @regionvoices5228 ปีที่แล้ว

    Hello Mate Will the cause the engine to start idle then when you raise the RPM it dies or hesitates then runs Hard to start when hot

    • @VintageEngineRepairs
      @VintageEngineRepairs  ปีที่แล้ว

      Hmmmm possibly, it can be other symptoms too though! I’d suggest it’s more likely an air leak or scored piston. Have a look as the piston skirt through the exhaust port. It should be nice and clean, no scratches or vertical scoring!

    • @regionvoices5228
      @regionvoices5228 ปีที่แล้ว

      @@VintageEngineRepairs Oh geez Don't jinx me Put a new OEM carburetor on it last season & ran great Occasionally would backfire thru the carburator when shut off It has spark but its faint It doesn't make a CRACK or POP sound its just real faint These small.engines are the devil

  • @CTSCAPER
    @CTSCAPER ปีที่แล้ว

    Do you know what kind of tree that is behind you? It's gorgeous!

    • @VintageEngineRepairs
      @VintageEngineRepairs  ปีที่แล้ว +1

      Bottle brush :)

    • @CTSCAPER
      @CTSCAPER ปีที่แล้ว +1

      Thank you! I was just watching videos about Multimeters, so I'll have to watch your video but those red flowers caught my eye first..@@VintageEngineRepairs

  • @chrispalmer9650
    @chrispalmer9650 9 วันที่ผ่านมา

    Accurately articulated with great presentation.

  • @threejackcity4471
    @threejackcity4471 7 หลายเดือนก่อน

    Good, thorough video, as always but I suspect I'll have to watch it multiple times to have a grasp. In the meantime, a quick question. I recently bought an older Echo chainsaw. The seller mentioned something about the coil, so I assumed it would be a spark problem, but starts right up and runs great. The problem is that the kill switch doesn't work. In true backyard mechanic fashion, I replaced the switch which was quite loose. That didn't fix the issue. Could a faulty ignition coil cause the problem I described? Thanks

    • @VintageEngineRepairs
      @VintageEngineRepairs  7 หลายเดือนก่อน

      Hmm very unlikely, it’s more likely a damaged wire mate. Get access to the coil and trace both wires to find the fault :)

  • @joe-fix-it9046
    @joe-fix-it9046 ปีที่แล้ว +2

    Awesome video, great explanation on how to test the coil and where to set the meter. Thanks

  • @ermannodangelo1062
    @ermannodangelo1062 ปีที่แล้ว

    Good video, what is that plant behind you.

    • @VintageEngineRepairs
      @VintageEngineRepairs  ปีที่แล้ว

      I’m not sure honestly! It’s so beautiful though I can’t resist using it as a back drop while it’s in flower :)

    • @treecycle4631
      @treecycle4631 ปีที่แล้ว

      @@VintageEngineRepairs It's a Callistemon or common name Bottle Brush.

    • @VintageEngineRepairs
      @VintageEngineRepairs  ปีที่แล้ว

      @treecycle4631 thank you :)

  • @someguy1717
    @someguy1717 ปีที่แล้ว

    Is this only applicable with older units? I ask because I tested two brand new ones yesterday after watching this video. Secondary coil - 5.5k, primary coil 8.5 megaohms. After scouring the web someone said the circuitry in newer ones prevents an accurate reading of the primary.

    • @VintageEngineRepairs
      @VintageEngineRepairs  ปีที่แล้ว

      It can do! Every coil is different, test both sides, check everything mentioned. Still no spark, replace coil.

  • @mzunnurain
    @mzunnurain 5 หลายเดือนก่อน

    Our push mower starts using recoil pull cord but not electric start. Replaced battery and bought a used starter. Advice?

    • @VintageEngineRepairs
      @VintageEngineRepairs  5 หลายเดือนก่อน

      When you turn the key, do you get anything? Clicking?

    • @mzunnurain
      @mzunnurain 5 หลายเดือนก่อน

      @@VintageEngineRepairs no key, no clicking. Just a push button. The flywheel turns once and stops.

    • @VintageEngineRepairs
      @VintageEngineRepairs  5 หลายเดือนก่อน +1

      Hmm sounds like either the compression release isn’t working, maybe you have a seized bearing in the stater, it could be a dirty commutator, poor connection somewhere etc

  • @farmerbaker
    @farmerbaker ปีที่แล้ว

    I am getting .389 on the primary is that close enough to .5 ?

  • @BalGo89
    @BalGo89 ปีที่แล้ว +3

    Another great video Tom! I have been testing some Stihl coils and I was getting those weird readings. I’ll be sure to check them again.

  • @xxjoetaylorxx
    @xxjoetaylorxx 7 หลายเดือนก่อน

    I have a briggs and stratton opposed twin 16.5 it ran good cut haft the lawn shut it off and would not start again tested coil says it's bad sence then I've tryed 6 coils on it and everyone of them went bad on the 3 attempt I disconnected all the wires to the motor except the starter cable still nothing have you ever heard of anything like this ?

    • @VintageEngineRepairs
      @VintageEngineRepairs  7 หลายเดือนก่อน +1

      I haven’t I’m afraid, but also I haven’t worked on one, are they genuine Briggs coils or aftermarket Chinese clones?

  • @nickush7512
    @nickush7512 9 หลายเดือนก่อน

    I think that I have thanked you before, and if so, never mind !! Thanks Bro, I had this video saved ready for when I needed it, and today, I needed it, and now that I have actually done it, I will most likely remember it.... Thanks, again again....

    • @VintageEngineRepairs
      @VintageEngineRepairs  9 หลายเดือนก่อน +1

      Awesome! That’s great news :) you’re welcome!

  • @Mechanicturfgear
    @Mechanicturfgear 3 หลายเดือนก่อน +1

    I use to test them but found many ok till they heat up when in use . Will run when cold but dies after running for a while and won’t start (check fuel tank venting ) . Also see a mention of do magnets go bad on flywheel . Although super very rare they can lose magnetism . Just use a screw driver to test if it pulls to it is most likely fine . I have personally have never seen this so to me is a myth . Good info though for a dead coil scenario

    • @VintageEngineRepairs
      @VintageEngineRepairs  3 หลายเดือนก่อน

      Yep spot on re magnetism loss! Thanks for watching :)

    • @juliodjtakeovervelez7182
      @juliodjtakeovervelez7182 3 หลายเดือนก่อน +1

      I have the same issue,I can rev high and runs great till warms up,after about 5min starts to back fire and not hit on all cylinders then dies,till cools off,thrn can repeat

    • @VintageEngineRepairs
      @VintageEngineRepairs  3 หลายเดือนก่อน

      @@juliodjtakeovervelez7182 that sounds like a coil

  • @fredwilliamsonmiller7214
    @fredwilliamsonmiller7214 ปีที่แล้ว

    Tom, I have been watching and re-watching your video on resistance values in small engine ignition modules, specically a 2 stroke module. The secondary measurements on my original module =4100 ohms, while the new module = 2600 ohms. The primary values original module = >30 Mohms ( fritzed?), new module = weird values depending on multimeter scale, 29.5Kohm to 201Kohm to 122 Kohm. I can not rationalize the electronic circuitry impact on the primary readings. Nether coil seems to create spark at my older plug and brand new plug. Any advice here?

    • @VintageEngineRepairs
      @VintageEngineRepairs  ปีที่แล้ว

      Hey, did you remove all possible coating that may be on the coil armature giving you high readings? Remember that, as mentioned, the electronic circuitry on the primary side can affect the resistance readings you’re getting. Are these coils both Chinese clones? What machine is it on?

  • @isaacpierrelawrence2573
    @isaacpierrelawrence2573 8 หลายเดือนก่อน +21

    If anyone is wondering about the tree behind him it's a wallum bottlebrush... Anyways...

    • @VintageEngineRepairs
      @VintageEngineRepairs  8 หลายเดือนก่อน

      Haha everyone seems to be asking me, thanks for the clarification, it’s rather dull now we’re in autumn!

    • @alanhow3575
      @alanhow3575 7 หลายเดือนก่อน +1

      Great Aussie ‘bottle brush’

    • @jaysaw8151
      @jaysaw8151 5 หลายเดือนก่อน

      Iv got one here in FL almost lost it in 2022 it got down to 17°f with harsh humidity i was real upset ..one a few trees I got left since hurricane Michael...I got a old bench beside it and use it as shade since it came back after me cutting it almost all the way down ..they are tuff and come back strong

    • @SiteReader
      @SiteReader 5 หลายเดือนก่อน

      Oh, thanks. I was wondering too. Don't have those over here in New England, USA.

    • @rockiemountin7535
      @rockiemountin7535 3 หลายเดือนก่อน +1

      I was thank you very much. That’s a beautiful tree

  • @eojkivalcav6679
    @eojkivalcav6679 ปีที่แล้ว +1

    If a simple coil with no electronics, I have taken a 6-volt dry cell and hooked up a ground to the armature, hooked up a spark plug, and of course, ground it. Then briefly touch the positive connection and watch the spark plug and if it has a spark, it is probably good. Just don't hold the wire on the primary just touch it like a set of points are opening and closing.

  • @haneyoakie14
    @haneyoakie14 ปีที่แล้ว +2

    Good information well delivered. Thank you Tom. I will be referencing this video again and again. I bought a box of coils at auction dirt cheap. $20 for about 20 coils, mainly Briggs Quantum and Classic types by casual observation. I will be testing them to see which are keepers.

    • @VintageEngineRepairs
      @VintageEngineRepairs  ปีที่แล้ว +1

      Amazing find!! I’m pleased for you, that’ll be handy. Glad you enjoyed the video :)

  • @orweyztungchiu5819
    @orweyztungchiu5819 ปีที่แล้ว

    Very comprehensive coverage on ignition coil testing - wish I had seen it years ago. I'm thinking I've thrown out many good ones based on faulty testing criteria. Cheers

  • @alexsmith7696
    @alexsmith7696 7 หลายเดือนก่อน

    Is it possible the performance of a coil would be affected by heating up? Say after 20min of riding the bike?

    • @VintageEngineRepairs
      @VintageEngineRepairs  7 หลายเดือนก่อน

      Yes absolutely! When a coil is on its way out, they tend to present their issues when warm and run nicely when cold.

  • @larrywhitesell4139
    @larrywhitesell4139 5 หลายเดือนก่อน

    I am confused as you said test resistance and not continuity but my multimeter only has a setting for continuity.

    • @VintageEngineRepairs
      @VintageEngineRepairs  5 หลายเดือนก่อน

      There should be a select button. Set it to continuity then push the select button to switch between continuity and resistance.

  • @larrywhitesell4139
    @larrywhitesell4139 5 หลายเดือนก่อน

    Do the flywheel magnets go bad?

  • @ericroman9126
    @ericroman9126 3 หลายเดือนก่อน

    Fantastic video. I was ready to look into buying new coils because of off readings due to my amateur mechanics. I didn't know I should chose the lowest ohm setting for primary testing and it didn't occur to me to subtract any prior ohm showing before the actual test. Thanks man.

  • @mikec2173
    @mikec2173 5 หลายเดือนก่อน

    thanks for a very well prepared and executed tutorial. Not a moment wasted! Not a single umm or errr. I learnt more than ever about this diagnosis. In my case it was a faulty ceramic resistor in the sparkplug boot. Not cracked. Looked a tiny bit discolored. Found after all the hassle of an engine pull-down for coil testing

    • @VintageEngineRepairs
      @VintageEngineRepairs  5 หลายเดือนก่อน +1

      Thank you for the kind words! I’m pleased you enjoyed it :) ahh yes those pesky resistors!! Good find, well done :)

    • @mikec2173
      @mikec2173 5 หลายเดือนก่อน

      @@VintageEngineRepairs have you considered US Presidential debating??😁😁😁

    • @VintageEngineRepairs
      @VintageEngineRepairs  5 หลายเดือนก่อน

      🤣😆 I’ll leave that to the …experts :)

  • @mickl8212
    @mickl8212 9 หลายเดือนก่อน

    One thing to note, I tested a coil on my Honda B16A2 engine. The readings were in spec but the engine wouldn't fire. I purchased a new coil after confirming the primary side trigger was switching. The engine fired up straight away after fitting the new coil.
    Same goes for coil on plugs on my Yamaha R6, was misfiring at 12000rpm on track, the readings were in spec both hot and cold. I bought and fitted new coils, the bike now revved through 12k and onto 15k whilst accelerating.

    • @VintageEngineRepairs
      @VintageEngineRepairs  9 หลายเดือนก่อน

      You’re absolutely right! You can have coils that are within spec, but the electronics that control spark timing etc can be bad and that will cause a misfire or non sparking coil :) this is just one of the tests we can do, at home, to get an idea of a good or bad coil.

  • @MegaGuitarpicker
    @MegaGuitarpicker 9 หลายเดือนก่อน

    Very helpful! Thank you!

  • @AllanSmith-e5m
    @AllanSmith-e5m 23 วันที่ผ่านมา

    This is only a very basic test and I don't place much value on testing coils with a multimeter myself.
    If you are suspecting a bad coil then the surest way of testing it is replacing it with a known good coil. If problem goes away then you know the original coil was bad.
    The reason a multimeter test on a coil is generally not really useful is that a multimeter operates on a very low voltage whilst the coil itself generates on a high voltage.
    High voltage can travel through carbonized coil lacquer or jump creating partial coil shorts. The other thing that can happen is that the windings expand when the coil gets warm and if the lacquer on the copper windings of the coil is damaged this can short it, whereas when it is cold it functions normally.

    • @VintageEngineRepairs
      @VintageEngineRepairs  23 วันที่ผ่านมา +1

      Thanks for sharing :)

    • @AllanSmith-e5m
      @AllanSmith-e5m 22 วันที่ผ่านมา

      @@VintageEngineRepairs You're welcome, thanks for sharing your knowledge also :)

  • @悟入木三分
    @悟入木三分 2 หลายเดือนก่อน

    multimeter test can't apply to some ignition coils which a semiconductor set in the primary winding. You test the resistance of primary which could be read like open circuit and dead, but actually it's because of its planted components.

    • @VintageEngineRepairs
      @VintageEngineRepairs  2 หลายเดือนก่อน

      I bring this up and explain how to test if the semiconductor material is creating false readings 👍🏻

    • @悟入木三分
      @悟入木三分 2 หลายเดือนก่อน

      the best is to put out typical circuits inside of primary winding. Thank you.

  • @garygerard4290
    @garygerard4290 10 หลายเดือนก่อน

    thank you for this information - I've saved it to my favorites

  • @treecycle4631
    @treecycle4631 ปีที่แล้ว

    Will tuck this one away for future reference. Thanks for all the info you provide for us.

  • @mikespain8655
    @mikespain8655 ปีที่แล้ว

    Excellent explanation, I enjoy your channel. I have replaced several ignition coils this year for customers.

  • @chandrakantindapurkar8738
    @chandrakantindapurkar8738 9 หลายเดือนก่อน

    Good explanation of HT coil
    Thanks a lot

  • @ColinWatters
    @ColinWatters 9 หลายเดือนก่อน

    Ive just replaced a faulty coil on a 21HP B&S twin. The working coil has a secondary of about 6k Ohms, the other faulty coil has a resistance of around 3k Ohms.

    • @VintageEngineRepairs
      @VintageEngineRepairs  9 หลายเดือนก่อน

      Quite a difference! It’s interesting to see something like that :) glad you got it sorted!

  • @tinkeringtaylor3053
    @tinkeringtaylor3053 ปีที่แล้ว +1

    Great information Tom 👍

  • @GuysPlayingWithTools
    @GuysPlayingWithTools ปีที่แล้ว +1

    Good video, good should help people

  • @slingshot909
    @slingshot909 2 หลายเดือนก่อน +1

    After watching this, I found a bad coil, now I have a running chainsaw, thank you!

    • @VintageEngineRepairs
      @VintageEngineRepairs  2 หลายเดือนก่อน

      You’re welcome! Stunning car in your thumb nail picture!!

  • @honeybadgerhoneyb4422
    @honeybadgerhoneyb4422 ปีที่แล้ว

    You should also test the leads. resistence in leads ???

  • @mr1pearl
    @mr1pearl ปีที่แล้ว +1

    I saved this one Tom I want to give this a try ! Not good at the electrical side of small engine repair 🤷

  • @kenhilson786
    @kenhilson786 2 วันที่ผ่านมา

    How about 15 mega ohms on the primary?

  • @Jmoe55
    @Jmoe55 ปีที่แล้ว

    Great video! Well explained and to the point!

  • @ddyeo503
    @ddyeo503 9 หลายเดือนก่อน

    I have an old Stihl 041 power saw with electronic Sweden ignition. there is also a German electronic ignition on some of them. And I have 3 parts saws I keep robbing electronic ignitions to keep the spark working. But one by one they fail over the years. There is a coil and it is attached to another part that picks up the magnetic signal from the flywheel. But these 2 parts are no longer available from Stihl. But all 3 coils test at around 1752 ohms which seems very high. Maybe you could test coils from an old 041 Stihl saw and show us how,,,,,,,,,,,,,,,I had to update to a 046 saw, but would like to get the 041 working again,,,,,,,,,,,,

    • @VintageEngineRepairs
      @VintageEngineRepairs  9 หลายเดือนก่อน

      Coils are generally very reliable, I believe the 041 is on points ignition isn’t it?

  • @michaelspencer301
    @michaelspencer301 ปีที่แล้ว

    Excellent video. That's more about an ignition coil I've heard from anyone. Thanks 😊

  • @cambodianexpress8557
    @cambodianexpress8557 หลายเดือนก่อน

    Hey, thanks so much... you had the best explanation of all the Yt's I looked. Especially needed the different values for 2 & 4 stroke coils. 👍

  • @jaysaw8151
    @jaysaw8151 5 หลายเดือนก่อน

    Thanks for the tip on testing coils ..iv got a lot of machines..week or no spart

  • @miketrissel5494
    @miketrissel5494 9 หลายเดือนก่อน

    Nice video - thanks. What is the name of that beautiful red blooming tree behind you, and since it is blooming now, are you from Australia. Mike Ohio USA

    • @VintageEngineRepairs
      @VintageEngineRepairs  9 หลายเดือนก่อน

      Hey! Yes it’s summer in Australia right now :) I’m here, yes! It’s a bottle brush tree, isn’t it stunning! I couldn’t resist it as a backdrop:)

  • @Big_Johns
    @Big_Johns ปีที่แล้ว +2

    Nice job Tom, thanks for the explanation. 👍

  • @almclean4835
    @almclean4835 ปีที่แล้ว

    Great video, very informative

  • @kraftzion
    @kraftzion 6 หลายเดือนก่อน

    Well I got 25.5 ohms primary and 4736 secondary on the coil I replaced. Here's weird for you. If I put the spark plug against the head I wouldn't get a spark. If I put my finger in between the sparkplug and the head I would.

    • @VintageEngineRepairs
      @VintageEngineRepairs  6 หลายเดือนก่อน

      How interesting! I have no idea about that haha. Thanks for sharing though!

  • @alexsmith7696
    @alexsmith7696 7 หลายเดือนก่อน

    Thank you. I’m hoping that may solve my problem. My motocross bike runs perfectly well for 15-20 min then dramatically looses power. Sounds like it’s choking

    • @VintageEngineRepairs
      @VintageEngineRepairs  7 หลายเดือนก่อน

      Hey :) it could very well be ignition coil. There are other electronic components like stator windings and ecu’s that can also fail. If you get hold of the service manual, you can check the resistance values of each and find if any are out of specification. Hope this helps!

  • @DK-jt6be
    @DK-jt6be 4 หลายเดือนก่อน

    Great explanation!

  • @darrenwardell3079
    @darrenwardell3079 10 หลายเดือนก่อน

    Brilliant many thanks

  • @wrench71
    @wrench71 ปีที่แล้ว

    You didn't state what a normal reading between the kill terminal and HT terminal should be when checking for electronics.

    • @VintageEngineRepairs
      @VintageEngineRepairs  ปีที่แล้ว

      There isn’t one

    • @wrench71
      @wrench71 ปีที่แล้ว +1

      Maybe you can clarify. At 6:55 you are testing between the "kill tab" and the HT terminal. You then state "If the resistance value between the armature and the HT lead or barb is correct, but the resistance value between the kill switch or kill tab and the HT lead or the barb is incorrect, then you know that it's more than likely........" How do I know if the resistance value between the kill tab and the HT lead is incorrect?

    • @VintageEngineRepairs
      @VintageEngineRepairs  ปีที่แล้ว

      @@wrench71 if it’s reading in the kohms or mohms like is shown 👍

  • @JackdeDuCoeur
    @JackdeDuCoeur ปีที่แล้ว

    Superhelpful! Thanks

  • @jimbola77
    @jimbola77 ปีที่แล้ว

    awesome man thank you for sharing.

  • @user-rs8zg8ey2b
    @user-rs8zg8ey2b ปีที่แล้ว +1

    You completely disregarded secondary insulation breakdown. The secondary winding can and most times look normal, but at high voltage it breaks down. A multimeter will not show you if this is an issue.

    • @VintageEngineRepairs
      @VintageEngineRepairs  ปีที่แล้ว

      If the insulation breaks down it will show a lower resistance value. Thanks for watching !

    • @user-rs8zg8ey2b
      @user-rs8zg8ey2b ปีที่แล้ว +1

      @@VintageEngineRepairs sorry, the insulation only breaks down at high voltage (flash over), not with the 2v applied with the meter in ohms.

    • @VintageEngineRepairs
      @VintageEngineRepairs  ปีที่แล้ว

      Ohhh yes, ideally coils will be tested by running a high enough current through on a test stand. We can only work with what we have at home :)

    • @d614gakadoug9
      @d614gakadoug9 ปีที่แล้ว

      @@VintageEngineRepairs
      No, a shorted turn cannot be resolved by resistance measurements. A single shorted turn can make the coil non-functional.
      A "ring test" will detect shorted turns, but it isn't something that is easy to do without more sophisticated equipment.

  • @traviscarr7930
    @traviscarr7930 ปีที่แล้ว

    Good video Tom. See you at work sometime buddy.

  • @davidstar4156
    @davidstar4156 7 หลายเดือนก่อน

    the best video out there...coils suck.

  • @joelmollenkopf3767
    @joelmollenkopf3767 ปีที่แล้ว

    Excellent

  • @justinlassiter7671
    @justinlassiter7671 7 หลายเดือนก่อน

    what kind of tree is that behind you?

    • @VintageEngineRepairs
      @VintageEngineRepairs  7 หลายเดือนก่อน

      Bottle brush 👍

    • @justinlassiter7671
      @justinlassiter7671 หลายเดือนก่อน

      @@VintageEngineRepairs absolutely beautiful. thanks and love your content

    • @VintageEngineRepairs
      @VintageEngineRepairs  หลายเดือนก่อน

      @justinlassiter7671 thanks for the kind words words and feedback :)

  • @A3Kr0n
    @A3Kr0n 10 หลายเดือนก่อน

    I stick the wires into the mains and if I see a spark I know it was good.

  • @texasjherrera
    @texasjherrera 4 หลายเดือนก่อน

    Great video

  • @roryheggie7633
    @roryheggie7633 6 หลายเดือนก่อน

    Great video cheers

  • @chrispomphrett4283
    @chrispomphrett4283 ปีที่แล้ว

    Buy a 500volt megger to check insulation breakdown resistance.

    • @VintageEngineRepairs
      @VintageEngineRepairs  ปีที่แล้ว

      Thanks, I’ll look into it 👍

    • @d614gakadoug9
      @d614gakadoug9 ปีที่แล้ว

      That won't help if you have a shorted turn in one of the windings, only if you have breakdown from one winding to the other or to the core.

  • @allanpatterson7653
    @allanpatterson7653 2 หลายเดือนก่อน

    Using a tool that measures resistance by using an AC signal rather than a DC voltage. A shorted turn is not detectable using a DC voltage

    • @VintageEngineRepairs
      @VintageEngineRepairs  2 หลายเดือนก่อน

      It’s the way stihl recommends you test their older coils. The only reason they don’t on the modern ones is due to the reasons I have mentioned and there is a work around.

    • @allanpatterson7653
      @allanpatterson7653 หลายเดือนก่อน

      @@VintageEngineRepairs interesting. I observed the laminated iron pieces rust between layers . The reason the core is many layers insulated electrically is because of Eddy currents.
      If a pathway between the plates can move 360*degrees it quenches the magnetic field.
      Clean it off give it quick shot of clear lacquer and away you go.
      Some of the multi electrode super plugs allow too much current and can melt the winding. Thanks for taking the time to post.

  • @mrantek7373
    @mrantek7373 8 วันที่ผ่านมา

    Love your accent mate. Similar to prof. Brian Cox 😉

  • @clintstevenson1214
    @clintstevenson1214 ปีที่แล้ว +3

    Another excellent video! As you know, you can test resistor spark plug resistance too. :-)

  • @adnacraigo6590
    @adnacraigo6590 10 หลายเดือนก่อน

    What is that beautiful tree you are sitting under?

  • @juliodjtakeovervelez7182
    @juliodjtakeovervelez7182 3 หลายเดือนก่อน +1

    Mine work fine until about 5 minutes then they start falling

  • @buddyhaywood8469
    @buddyhaywood8469 6 หลายเดือนก่อน

    What is that tree

  • @Ebooger
    @Ebooger วันที่ผ่านมา

    Major error in this video: If there's only ONE shorted turn in either the primary or secondary windings, the DC resistance measurement will be virtually unaffected, but the coil's spark output will be reduced to near zero. An ignition coil is an inductor, not a resistor, and must be test as such. You need to measure impedance (Z), not resistance, which will vary with frequency. This is why, for most D-I-Y circumstances, substitution is usually the easiest way to go.

  • @7Toki777
    @7Toki777 ปีที่แล้ว

    Thank you!!!

  • @hiylegonfaa8176
    @hiylegonfaa8176 10 หลายเดือนก่อน +1

    WoW

  • @luvmechanix
    @luvmechanix ปีที่แล้ว

    Multimeters arent really accurate in the .5 ohm range. It could be a dead short and you would never know it.
    It's better just to swap it out and see

  • @phillipcleaver7063
    @phillipcleaver7063 8 หลายเดือนก่อน

    Thanks mate , I,ve got an 85 year old Villiers mk10 that is giving everybody mixed up with it absolute hell , bad compression despite valves being newly lapped in & gapped , ( bore belled out ) , no spark , previously severely butchered in a failed attempt to get an obscure flywheel off etc . I,ll use your method to test the coils , & go from there . Much obliged , & I,ve clicked the buttons .

    • @VintageEngineRepairs
      @VintageEngineRepairs  8 หลายเดือนก่อน

      Thanks Phillip, I restored a mk10, they’re an amazing machine. Solid, reliable, strong, well built! Good luck with yours!

  • @bustersmith5569
    @bustersmith5569 ปีที่แล้ว

    👍

  • @pneulab
    @pneulab ปีที่แล้ว

    This will not test insulation breakdown.

  • @rickhunt3183
    @rickhunt3183 10 หลายเดือนก่อน

    If you're married you can tell your wife to put her finger in the top of the spark plug and give the recoil starter a pull see what happens. You'll know if it has a good spark.. There's actually a spark tester you can buy very cheap. Sometimes a meter will show a good coil but it will have a voltage leak and arc internally or the spark is weak. Always check the distance between the coil and the flywheel. The correct distance should be the thickness of a business card. It's important to set the distance after removing a coil. While it's good to use a feeler gauge, a business card will work just fine.

    • @VintageEngineRepairs
      @VintageEngineRepairs  10 หลายเดือนก่อน

      Ha! I try and stay out of the dog house haha

  • @mikeadler434
    @mikeadler434 ปีที่แล้ว

    👍👍

  • @richardcornelius1050
    @richardcornelius1050 3 หลายเดือนก่อน

    This is a useless test procedure .
    These style coils can fail at normal operating temperature and work again and again when cooled off .
    Your results are Inconclusive at best .

  • @geoeconomics5629
    @geoeconomics5629 7 หลายเดือนก่อน

    If you use multimeter 90% of the coils will check
    Ok

    • @VintageEngineRepairs
      @VintageEngineRepairs  7 หลายเดือนก่อน

      It’s just one way to get an idea of the condition of them.

  • @ALed-j7u
    @ALed-j7u 2 หลายเดือนก่อน

    too bad most gardening equipment is 2 stroke

    • @VintageEngineRepairs
      @VintageEngineRepairs  2 หลายเดือนก่อน

      Noooo that’s the best thing ;) I love 2 strokes way more haha