I’ve been building 2 stroke engines for nearly thirty years and can tell you now that them crank bearings need replacing I could hear they were gone straight away, also the rod is incorrectly installed as thrust washers are missing would also check crank alignment. Cylinder and head have been decked which is causing the the piston to get squashed. Double up on base gaskets will solve this which is a pretty standard thing to do is this situation. Also when checking squish don’t use wire so thick as this could of caused damage to the piston which would make rings stick
It’s when the mating surfaces of a cylinder, cylinder head or crankcase get damaged due to people using screwdrivers to separate the parts. You then machine a very small amount of material off to make surface flat again. When sound this to a cylinder it can cause problems if you don’t know what your doing. That’s why the piston is sitting higher than the cylinder which can be fixed by using two base gaskets. When you buy a gasket set for a Ktm they come with 3 different thickness base gaskets to adjust the compression ratio which comes in handy also if cylinder has been decked. Hope this helps
@@jimnewell5472 would thickening up the base gasket alter the port timing ? this is an issue with aprilia rs 125s and some builders lower the squish by machining the top of the cylinder.
@@gtisid Joe would need to put a degree wheel on, and figure out where the port timing is at, compare that to a stock unmolested motor and go from there. Nobody knows whether to add thicker gaskets or machine top of cylinder b.c. nobody knows what's been done, and where the port timing is at. I'm an at home diy builder and even I know that lol.
If your piston is above deck upon assembly(clay the piston to verify clearance), make a spacer plate of the same thickness(and also compensating for gasket thickness on either side)and get the deck height set properly. The bottom end is not your problem if the crank rotates smoothly in the cases. You would feel a sloppy bearing. That con rod is perfect, it is centered on the crankpin by the piston itself. Suzuki has done that for years with many of their 2-stroke engines. You could get a 0.020" thickness spacer made from copper, check with Cometic or other mfg. companies. That's what I think your main problem is. You should also be able to hone that cylinder out and have it work correctly, and water pumper 2-strokes actually do better with more piston clearance than an air-cooled engine. I discovered this with a CR500 in late '80's setting one up for desert racing, had to clearance the piston at least 0.0015 more than recommended and also built a deck plate to bolt on in place of the cylinder head which made for a true round bore when the head was torqued on. That bike did an honest 115 mph and never melted even at top end on the mainjet. Great content, Joe, keep up the good work and the good fight reviving these quads and dirt bikes!
Crazy how there doesn’t seem to be anything wrong with the bottom end. But there has to be a reason why it’s eating Top ends. Amazing job as always. Really looking forward to seeing it up and running again
The cylinder has been "decked" and the position is hitting the head gasket ever so slightly....that why the ring lands were smashed along with allowing a bit of coolant into the bore and caused the scoring.....I've been through this on a lt250 that had a bunch of cylinder work, double up that base.
the side play is not right, there need to be washers between the conrod and the crankshaft because the conrod is led by the washers, if it moves to much your piston will tilt in the cylinder. maybe get some engine drawings and see what is missing i would do that first. but the washers definetly need to be there. btw happy new year
You need to get a "telescoping guage set" (Harbor Freight) or maybe even a newer digital one and get the correct size to measure your bore. Get out a sheet of paper and measure top, middle, closer to the bottom. Then turn another 30 degrees and measure all 3 again -do this for a full 360 deg. =Looks like a cold seizure and not enough clearance. Or this cylinder has ovaled out due to being resleeved to many times (most likely the case). You can only resleeve a two-stroke 1-2 times before it starts to oval out. Find out what the cylinder specs are from the Suzuki LT500 manual.
@@enallane5538 No even with a new sleeve the heat warped cylinder will "oval" it. =You can only resleeve a cylinder so many times. There are sleeves that can be replaced and locked in or the older 4 strokes with the thick sleeves.
Two issues. First I believe your cylender has been decked a little to far and is causing the piston to hit the head. I'd throw a thicker base gasket on to help. Second I have never seen a crank without washers on each side. Alot of play there. Yes it's normal for the crank to move side to side a bit however that was ALOT of play.
Clearly you know nothing about the quadzilla cranks they have thrust washers on the piston and of the connecting rod not the crank end of the connecting rod completely shows your inexperience and non-knowledge of two strokes
@@razza219 clearly you and the person that you agreed with know nothing about what you're talking about Suzuki cranks on quadzillas don't have thrust washers on the big end of the connecting rod they have thrust washers on the piston side of the connecting rod or the small end whatever you want to call it the only way to get rid of those thrust washers is to run a piston from an RM 250 or rm500 depending whether you have an LT250R or lt500r but both those bikes from Suzuki have the thrust washers on the small end of the connecting rod completely shows your inexperience and lack of knowledge
Here we go, so the top of the piston touches the head gasket/head as it expands and heats up when running causing it to knock the ring grooves closed making the rings stick/seize. Thats just my take on this, so the piston needs to be trimed or spaced. Good luck 🤙🏻
Good stuff Joe and that you're not giving up. This engine problem is proving to be an interesting and worthwhile exercise in failure analysis and theories, Engine has not "blown up" it has seized, a "blow up" would mean there has been explosive activity, you then usually need replacement cases or cylinder and cubic dollars.
Hey Joe, I think since you have had a lot of issues with this engine. It would be a great opportunity to show everyone how to complete a proper 2 cycle Leak down test after you reassemble prior to starting. That is one of the first things I do after buying a used 2 stroke. Keep up the great work!
I agree totally with Mark. It's screams at you what happened the piston sticks out way to high out the barrel. When you turned the engine over first rebuild and the engine locked up I would put my mortgage on the outside of the dome of the piston was hitting the head. You forced it round and it crushed the ring groves and if it was the top ring that was the sticky one then that would reinforce my theory as that took the impact. And of course when the engine got hot they could not centralise on the piston evenly and got the partial seizure.
Looks like a lot of side to side play on the connecting rod. I'd just download the lt500r manual and see the specs. I think it blew up because the cylinder was hitting the head.
Maybe you could raise the cylinder and head with a thicker cylinder gasket. When building mopeds sometimes that's required and it works, maybe it can woth on a 500 haha.
With those leaving the negative remarks I'll leave a big positive. I love your videos because of how thorough you are. You go through everything from top to bottom to find hidden issues. I work on these things too and I know from a recent purchase of a used clapped out bike it's just better to put your eyes on everything just like you are doing, ruling out everything. Keep up the awesome vids!
So I’m not going say anything crash but I’ve worked on lt500s for about 6 years and my opinion is that there is a stroker crank and stock cylinder, piston, and head causing the piston to slap the head and the symptoms are Knocks and cutoffs
Check and make sure your crank isn't separating. Just had one a 1990 cr 500 do it. It's had a rough life was an old Tomac ranch play bike, everyone rode it.
The crank might be out of balance, it happens when you use a hammer to drop the crank into the bearings, so when it's out of balance the piston moves weird in the cylinders thus blowing up
I'm in favor of the possibility that the piston to head clearance is insufficient. The head may have been "milled down", which would also cause higher compression and the need to run high octane gas. If this turns out to be the issue, can you measure to see how far out the cylinder the piston extends at full stroke, then stack head gaskets accordingly, to increase the piston to head clearance, and thereby, have the side-effect of lowering the compression back down to be able to use pump gas? Lots of "assumptions" in this comment, but just my .02. Good luck. Now I will watch the rest of the video!
Only gonna mention this because it was a problem I ran into on my first liquid cooled 80cc 2-stroke rebuild which required an overbore, and something I was looking for in the videos but was cut; I installed the head gasket how a tab on the gasket lined up to a cutout on the case but it in fact needed to be flipped so the tab didn't line up. The effect was the cylinder was getting starved for coolant because the small holes in it were where the big holes were supposed to be. The result was piston/cylinder scoring near the exhaust port within the first few minutes of running. Looked like a no-brainer but was actually a gotcha and to this day I wonder where I should have been able to find that info as even the repair manual wasn't detailed enough to note that orientation. Good luck, and that crank definitely needs some TLC.
Nice summary and coverage of possible issues from the comments. Get that cylinder lifted up with some base gaskets and jetting set properly and it should be good. As far as the cylinder height, there is usually an overall measurment from the mfg to verify how much its been milled. When the bottom of it gets shaved, it lowers it along with all the ports which totally messes up your port timing too. Raising it up will restore that and get you proper head clearance. Piston was probably lightly tapping the head which crushed the ring grooves and caused the piston scuffing.
Bottom end looks great. Looks like piston might be hitting the head gasket. And make sure your ring gap isn't to Small on next piston. Those cranks don't have thrust washers like modern cranks . Have thicker ones same size as bearing
Dang, someone who knows that Suzuki didn't use thrust washers on their big end rod bearings! The piston centers the rod on the crank. On the same page with you, 2 stroke rebuilder!
Probably need to stick with the junkyard salvage and avoid the performance quads if your not properly checking things and just throwing it together kinda winging it. Tolerances I believe wasn’t checked as everyone else said the first time it blew up.
He doesn't listen to anybody that actually has knowledge I know exactly why it blew up clearance when a piston scuffs on the four corners that is what's called a cold seizure the piston swells up faster than the cylinder can expand this is quite common with forged pistons and steel sleeved cylinders it's not quite as bad in plated cylinders as they can expand faster and you're 100% right he should stick to the junkyard salvage shit because he doesn't have the knowledge to build high performance quads where the very slightest clearance that's too tight and you're done I had a $2,000 Banshee Cub cylinder chip the plating in less than half an hour it was the players fault but shows you that things can happen on even expensive cylinders but he needs to take the quadzilla motor out of it put a Banshee motor back in it sell the quadzilla motor to someone that knows what they're doing and just beyond his way riding the Banshee a good built Banshee motor will put a way more power than a quadzilla motor any day no matter what porting is done to the quadzilla motor
@@mattstewart222 I do this stuff for a living I don't have time to worry about a goddamn camera and angles and editing and all that bullshit it would slow me down way more than the value of the video would ever be worth I can make 10 times as much money in the period of time it would take me to film I can make that money doing work and putting vehicles and ATVs out the door instead of worrying about filming every fucking thing
your right, it is difficult to see from this point of view, I am wondering if the center case gasket surface is good or not. yes, typically an air leak should make the motor idle hight but it is also possible to overcome than but running a larger pilot jet, especially if it is a small leak. I seem to remember that suzuki does not use a center case gasket but uses a special cement to seal that surface. If the motor was ever too hot it is not impossible that the center cases are warped just a little, just enough create a small air leak. good idea to replace the main bearing seals. I am wondering if someone milled either the cylinder to eliminate a warped base gasket surface, not impossible, I had one that did. I ended up dressing it by hand and then I ended up adding more gasket material to compensated for the difference. checking deck height would be important as well.(deck height = top of piston to top of cylinder at TDC Japanese bike typically do not have this issue but you never know who was in this motor before you or just what they were thinking. the other thought i had was that the cylinder was bore out of alignment. but since you had the cylinder done, that is unlikely.
Just to add to this some manufacturers shim con rods from bottom and some from top. If there is side to side movement at crank end then there should be little to no play at piston.
Still think crank bearing area moving at some point, may feel good and tight but I've seen it happen. 2 strokes are high rpm so they can do some wierd stuff.
Leave suggestion on what you think went wrong with this quad! I will be reading all replies! Thank you! Here is the piston I used to rebuild the quadzilla. Thinking about going with a different piston next time. Wiseco piston: amzn.to/33dKXx6 Please SUBSCRIBE and LIKE the video if you enjoyed! It really helps me out a lot! Check out my Instagram: 2_vintage_ Thank you for all the support!
@2vintage I guess you didn't see my message, I can tell you exactly what happened an why. When you get a cylinder back or even after honing. When you wash it you need to get your hand in there an scrub it clean. Swishing an rinsing won't get the left over from honing an boring. After you wash an scrub the cylinder use a clean paper towel an wipe it. It will leave black on the paper towel so you need to keep cleaning it till you wipe it an there isn't any black being left on the cylinder. If you don't the crud is abrasive left over from the honing an if it's not cleaned well you end up getting stuck rings an scratches. Just as you had happen. One other thing. When you drop a cylinder on you never want to twist it so that it lines up, by turning the cylinder like you did on that assemble causes the rings on one side to have the ring gap forced right against the ring gap center pin an will cause the rings to stick an cause cylinder scratching. I am sure that's the first time you have turned the cylinder like that an probably didn't know that's a no no. So just make sure you get the cylinder clean an check with the paper towel wipe an leave the reed cage an intake boot off when dropping the cylinder on. So it drops down lined up. On the piston smacking the head more time than not it's caused from a missing alignment shim causing the cylinder to be moved forward it back a couple millimeters but it could also be the other owner has the cylinder deck shaved a little. To fix that you just need to use a oem base gasket that has the small bead of black silicone on it, thicker or even doubling up 2 base gaskets to get more thickness. Then might have had the cases decked/ shaved because it had bad scratched or the replace one side of three case an had it done because they didn't line up even. Either way thicker base gasket will fix that. They do make different sizes so you can alter the squish band. Good luck, it's a cool machine I want to see you get it going trouble free.
I wonder if someone machined the sealing surface on the top of the cases. It is a trick to lower the cylinder and reduce transfer and exhaust port duration. Seems odd the bolt boss by the base gasket sealing surface wouldn’t have paint on it. Would result in the piston sticking out too far with a stock rod and piston compression height. I enjoy the channel!
Joe use a sharpie and color the head in and put it back on. Cycle the piston up and down a few times and pull the head back off and look for witness marks in the sharpie
The case to cylinder surface has been milled down a lot as you can see at 31:09 where the paint is missing or has been sanded down in the location where the top case bolt goes through.(see the base gasket surface closest to the camera? Beneath that you can see the paint is missing on the case top. You need to compensate for this with either 2 base gaskets or if they sell a thicker gasket.
Pull out the crank and have it rebuilt. This time with thrust washers. Then, and only then, have it correctly balanced. Eric Gorr is in Wisconsin, why would you spend your money any place else. The PO lied to you about the crank or the washers he installed got turned to metallic paste.
The lt500 doesn't have thrust washers on the big end of the rod just smaller thrust washers on the piston pin to align the rod on the crank. I believe the bottom of the cyl was machined down for the lower port timing or for a repair. If it were me I would get billet thrust washers and the correct wrist pin bearing for the thicker washers and then call cometic and get an array of base gaskets ranging from .020 to .059 to try and get the squish were it should be. Also I'd get a few different head gaskets in various thicknesses and get them for an overbored cylinder. Please put new crank bearing and seals in there while you have it apart.
Thanks to your quality video camera, I can see that the top of the case has been machined. The lowered cylinder is causing the piston to hit the head. You can notice this best by how close the raised print "... STROKE" is close to the machined surface for the cylinder base.
Before throwing more money at it, check that the connecting rod is truly straight. Easy and free to do. I thought the top looked a little tweaked. Just my 2 cents.
That bolt that you were having a hard time getting off or the nut I should say is reverse thread you're cranking it tighter you have to go the way you would normally tighten it up to loosen it reverse thread
Piston to bore was measured by the guy who did the cylinder, but not the ring end gap. Rings got warm, expanded and bound up on cylinder wall, scoring it, and losing compression
The thicker base gasket will help. Just one thing though. Make sure the counter balance is matched to the piston. There should be a guide on how to match it at least there is on cars. I've worked on many Honda preludes that have a counter balance similar to what you have. If they are not timed right and if they are not matched to the weight of the pistons and the crank they can destroy pistons, crack piston rings, over stretch the rods,and destroy crank and rod bearings and many more things. I would do some research into it if I were you. It might sound stupid but unfelt vibrations in an engine can cause stupid things to happen. Good luck. Hope you solve the issue.
So all things considered after watching the full vid… I would definitely say the piston is contacting the head just enough after warming up that it is being mushed down against the rings just enough to grab the rings and score the cylinder… I wouldn’t even attempt another start on that engine until you get a bit more clearance between the head.
Hey man I know you might eventually figure this out on your own but if Sabo happens to offer help with this engine you might wanna hear what he has to say 🤷🏼♂️
@@250race dude both these guys are good but Sabo is better, Sabo tears his engines down to nothing rebuilds it better. This guy he's good but he cuts a LOT of corners attention to the little details is non existent. Buys cheap parts off ebay, if this guy would go the extra mile and do things right he would be awesome. And one more thing I also think if he would get off the floor and work on a table or workbench he could do better. But you can lead a horse to water but you can't make him drink.
There were metal shavings in the crank area I would replace crank bearings n get OEM crank or connected rod kit there should never be any shavings in crank area
I personally agree with everything your saying dosent sound like it’s sucking air and the crank looks perfect this would stump me too man sucks it’s such a cool machine
The side to side play is completely normal, it’s just for lubrication purposes. I rebuilt one and had the same concerns with the side to side play but it’s all good.
I'm no keyboard warrior and I'm just posting my thoughts. I'd check if the rings are binding all around or just one or two spots, if they're binding all around somethings up with your piston to head clearance, if they're binding in just one or two spots then I would believe using the lead solder wire to check clearance caused the aluminium of the piston to warp and pinch the rings. You can check clearance of the grooves for the rings on the new piston too to check if they're not to tight for the rings you're using.
Maybe try to check cylinder head to piston clearance again. Is it normal for that case to look like it was machined down where the cylinder seats against it? Maybe try a thicker gasket?
My quadzilla on the factory sticker by the gas cap says to run it at 20:1 gas mixture. New oil probably can go leaner but on a new rebuild I would mix it rich anyway. The worst would be a fouled plug.
The crank bearing sounds rough, i would replace it. Some people are saying you are missing thrust washers on crank, a few are saying there are only smaller thrust washers on piston side of con-rod. Double up base gasket may get your piston squish correct
Could the rings also be hitting the gasket causing the ring issue? Did u check the gasket for contact marks? At the end of the running vid it seems like it was starting to seize or get tight. Wiesco pistons need a lot of clearance since they are forged and heat up different than the cylinder head..check the cooling system for equal flow around cylinder. Check the power valve operation..
Hard to see clearly but its looks like someone forgot the two washers on each side of the connecting rod(09160-24022) but i wouldn’t think that would cause the piston over travel, i think someone decked the cylinder or head to increase compression and got a little carried away.
That crank bearing thing can get spendy fyi. What isee it looks pretty solid but only has to spin a bit to throw rod up . Love watching you work, wish I had 3 of you here, I could actually run my shop and not be busy all the time...
I think it might have been running too lean and lacked a nice rich run-in session to seat the rings properly. Rapid heat increase with lack of lubrication would expand the rings to maximum tolerances 🤷🏻♂️🤷🏻♂️ always run richer on a fresh engine especially in cold environments 👌
I don’t know if it’s just me but That crank bearing sounds kind of loud! Might want to get the clay out and check your piston to head clearance .also check ring end gap? And totally agree I will put the crank seals in there while you’re there!
The next question Fuel mixture. Is is heat and or clearance? Is it jetted to lean? Do you need more 2stroke oil in the mix? Is it drawing air in after the carb? Like a manifold suction leak following the path of least resistance. Is the cooling system working Water pump, Rad and thermostat.
you just need an ali spacer and 2 gaskets. remember dont run piston too close to the head. because as soon as the bottom bearings get any play at all ... boom shes done either wrong rod. or the barrel has been shaved to much over the years. as you are thinking. you may need to ajust timing a tiny bit for performance. it will be fine.
Hope you get it fixed joe it's a nice quad seeing a lot of comments on washers are missing from the rod causing play in the piston plus thicker head gasket for clearance maybe something to look at mate a lot of good comments on this hopefully that's what the problem is take care and all the best 🔧🔧🔧👍👍
Holy shit! No smoke is no oil. If oil/fuel is 28:1, which is lots of oil for a 500. Then, way too lean on pilot jet. It's got squish, lots of it. That crank bearing sounded dry 27:05 when you moved it with your hand, while your trans bearings are silent. No oil from too lean on the pilot. it ran on the pilot the entire minute and piston scuff proves no oil. Start with a 50 pilot and let it foul a plug. Main in the 175 range and read the plug before WOT runs or it will squeak every time, if it's lean. It blew up on the road due to lean WOT A/F ratio. It hurt my soul when it squeaked. You can hear it. Been there, squeaked a couple too. Keep going!
The lower end of the connecting rod looks really sloppy (side to side) to me. Not sure what the measurement is suppose to be. That would be something I would check to reassure me. And would be curious on the thickness of the gaskets for the bottom and top of the cylinder since it does looks like the piston is possibly hitting the cylinder head and pinching the rings like you said. I would maybe go as far as reinstalling the "old" connecting rod if it's ok. A lot of money spent for 11 minutes of use so far. I feel for ya.
Is it the right rod? Did you check the model # of the rod? Could be too long which is why it hit the head. I would also make sure that all the bearings are flush with the case.
As everyone else has also said . check clearence to the head . missing thrust washers . but I am surprised noone has metioned the exhaust either. If that has been modified or changed to fit the motor into the banshee frame it may be flowing to much or nlt have enough back pressure. I'm sure you undsrstand how a 2 ztroke works but without that backpressure could cause you to run lean ... I do not think that is the issue with your "squished piston" but something to think about and just surprised noone else mentioned it
use some plastaguage and see how much crush you get on the top of the pistion, maybe u need to add a second base gasket to raise it up a wee bit. Too me the piston and bore dont seem right just by going by the marks it left on the cylinder wall, do u have calipers to measure that and check the clearance? I dont know about these newer bikes but back in the 80's we had some cylinders that could not be bored, maybe thats the case with this jug.
i have the same thing happening with my 1998 rm80, no it’s not blowing up but the crank has no washers on the side of the crank which i’d never seen before!!
I’ve been building 2 stroke engines for nearly thirty years and can tell you now that them crank bearings need replacing I could hear they were gone straight away, also the rod is incorrectly installed as thrust washers are missing would also check crank alignment. Cylinder and head have been decked which is causing the the piston to get squashed. Double up on base gaskets will solve this which is a pretty standard thing to do is this situation. Also when checking squish don’t use wire so thick as this could of caused damage to the piston which would make rings stick
What exactly does 'being decked' mean?
It’s when the mating surfaces of a cylinder, cylinder head or crankcase get damaged due to people using screwdrivers to separate the parts. You then machine a very small amount of material off to make surface flat again. When sound this to a cylinder it can cause problems if you don’t know what your doing. That’s why the piston is sitting higher than the cylinder which can be fixed by using two base gaskets. When you buy a gasket set for a Ktm they come with 3 different thickness base gaskets to adjust the compression ratio which comes in handy also if cylinder has been decked. Hope this helps
@@jimnewell5472 would thickening up the base gasket alter the port timing ? this is an issue with aprilia rs 125s and some builders lower the squish by machining the top of the cylinder.
@@gtisid Joe would need to put a degree wheel on, and figure out where the port timing is at, compare that to a stock unmolested motor and go from there. Nobody knows whether to add thicker gaskets or machine top of cylinder b.c. nobody knows what's been done, and where the port timing is at. I'm an at home diy builder and even I know that lol.
You are absolutely correct Sir!
If your piston is above deck upon assembly(clay the piston to verify clearance), make a spacer plate of the same thickness(and also compensating for gasket thickness on either side)and get the deck height set properly. The bottom end is not your problem if the crank rotates smoothly in the cases. You would feel a sloppy bearing. That con rod is perfect, it is centered on the crankpin by the piston itself. Suzuki has done that for years with many of their 2-stroke engines.
You could get a 0.020" thickness spacer made from copper, check with Cometic or other mfg. companies.
That's what I think your main problem is. You should also be able to hone that cylinder out and have it work correctly, and water pumper 2-strokes actually do better with more piston clearance than an air-cooled engine. I discovered this with a CR500 in late '80's setting one up for desert racing, had to clearance the piston at least 0.0015 more than recommended and also built a deck plate to bolt on in place of the cylinder head which made for a true round bore when the head was torqued on. That bike did an honest 115 mph and never melted even at top end on the mainjet.
Great content, Joe, keep up the good work and the good fight reviving these quads and dirt bikes!
Crazy how there doesn’t seem to be anything wrong with the bottom end. But there has to be a reason why it’s eating Top ends. Amazing job as always. Really looking forward to seeing it up and running again
The cylinder has been "decked" and the position is hitting the head gasket ever so slightly....that why the ring lands were smashed along with allowing a bit of coolant into the bore and caused the scoring.....I've been through this on a lt250 that had a bunch of cylinder work, double up that base.
Exactly what I was thinking. Needs a thicker base gasket, for whatever reason.
I agree, also if the rod is not to spec and is just a few thou long it will also jam the piston.
Correct
Wouldnt want to buy the correct parts or anything huh? Always some Moronic Clown with a half ass "fix", which ultimately fails. Ignorance abounds.
the side play is not right, there need to be washers between the conrod and the crankshaft because the conrod is led by the washers, if it moves to much your piston will tilt in the cylinder. maybe get some engine drawings and see what is missing i would do that first. but the washers definetly need to be there.
btw happy new year
exactly what i thought
Exactly!
Page 3-25 of the manual.
I agree. That's a bit too much side to side play.
Thought same thing
You need to get a "telescoping guage set" (Harbor Freight) or maybe even a newer digital one and get the correct size to measure your bore. Get out a sheet of paper and measure top, middle, closer to the bottom. Then turn another 30 degrees and measure all 3 again -do this for a full 360 deg.
=Looks like a cold seizure and not enough clearance. Or this cylinder has ovaled out due to being resleeved to many times (most likely the case). You can only resleeve a two-stroke 1-2 times before it starts to oval out.
Find out what the cylinder specs are from the Suzuki LT500 manual.
It wasn’t resleeved it was bored so I don’t think that would be the issue
by "resleeve" I assume you mean hone, because a resleeve would be a new cylinder that's perfectly round.
@@enallane5538 No even with a new sleeve the heat warped cylinder will "oval" it. =You can only resleeve a cylinder so many times. There are sleeves that can be replaced and locked in or the older 4 strokes with the thick sleeves.
Where r the thrust washers on the lower con rod bearings ? Not seeing any so will give side play creating twist
I was thinking the same thing thats way to much side play.
Two issues. First I believe your cylender has been decked a little to far and is causing the piston to hit the head. I'd throw a thicker base gasket on to help. Second I have never seen a crank without washers on each side. Alot of play there. Yes it's normal for the crank to move side to side a bit however that was ALOT of play.
100% right, that crank needs rebuilt
Clearly you know nothing about the quadzilla cranks they have thrust washers on the piston and of the connecting rod not the crank end of the connecting rod completely shows your inexperience and non-knowledge of two strokes
@@razza219 clearly you and the person that you agreed with know nothing about what you're talking about Suzuki cranks on quadzillas don't have thrust washers on the big end of the connecting rod they have thrust washers on the piston side of the connecting rod or the small end whatever you want to call it the only way to get rid of those thrust washers is to run a piston from an RM 250 or rm500 depending whether you have an LT250R or lt500r but both those bikes from Suzuki have the thrust washers on the small end of the connecting rod completely shows your inexperience and lack of knowledge
Here we go, so the top of the piston touches the head gasket/head as it expands and heats up when running causing it to knock the ring grooves closed making the rings stick/seize. Thats just my take on this, so the piston needs to be trimed or spaced. Good luck 🤙🏻
Good stuff Joe and that you're not giving up. This engine problem is proving to be an interesting and worthwhile exercise in failure analysis and theories, Engine has not "blown up" it has seized, a "blow up" would mean there has been explosive activity, you then usually need replacement cases or cylinder and cubic dollars.
Hey Joe, I think since you have had a lot of issues with this engine. It would be a great opportunity to show everyone how to complete a proper 2 cycle Leak down test after you reassemble prior to starting. That is one of the first things I do after buying a used 2 stroke. Keep up the great work!
I agree totally with Mark. It's screams at you what happened the piston sticks out way to high out the barrel. When you turned the engine over first rebuild and the engine locked up I would put my mortgage on the outside of the dome of the piston was hitting the head. You forced it round and it crushed the ring groves and if it was the top ring that was the sticky one then that would reinforce my theory as that took the impact. And of course when the engine got hot they could not centralise on the piston evenly and got the partial seizure.
Looks like a lot of side to side play on the connecting rod. I'd just download the lt500r manual and see the specs. I think it blew up because the cylinder was hitting the head.
Where you download it at going to need this when rebuilding mine
Your a great mechanic, don't even read the negative comments bro.ive seen you figure tough problems. Stay positive
Maybe you could raise the cylinder and head with a thicker cylinder gasket. When building mopeds sometimes that's required and it works, maybe it can woth on a 500 haha.
Yup
With those leaving the negative remarks I'll leave a big positive. I love your videos because of how thorough you are. You go through everything from top to bottom to find hidden issues. I work on these things too and I know from a recent purchase of a used clapped out bike it's just better to put your eyes on everything just like you are doing, ruling out everything. Keep up the awesome vids!
So I’m not going say anything crash but I’ve worked on lt500s for about 6 years and my opinion is that there is a stroker crank and stock cylinder, piston, and head causing the piston to slap the head and the symptoms are Knocks and cutoffs
Check and make sure your crank isn't separating. Just had one a 1990 cr 500 do it. It's had a rough life was an old Tomac ranch play bike, everyone rode it.
The crank might be out of balance, it happens when you use a hammer to drop the crank into the bearings, so when it's out of balance the piston moves weird in the cylinders thus blowing up
I would take the engine all apart and follow a diagram and make sure you have everything together like it was from factory
I'm in favor of the possibility that the piston to head clearance is insufficient. The head may have been "milled down", which would also cause higher compression and the need to run high octane gas. If this turns out to be the issue, can you measure to see how far out the cylinder the piston extends at full stroke, then stack head gaskets accordingly, to increase the piston to head clearance, and thereby, have the side-effect of lowering the compression back down to be able to use pump gas? Lots of "assumptions" in this comment, but just my .02. Good luck. Now I will watch the rest of the video!
Agree. You saved me lots of typing. Milled down.
Only gonna mention this because it was a problem I ran into on my first liquid cooled 80cc 2-stroke rebuild which required an overbore, and something I was looking for in the videos but was cut; I installed the head gasket how a tab on the gasket lined up to a cutout on the case but it in fact needed to be flipped so the tab didn't line up. The effect was the cylinder was getting starved for coolant because the small holes in it were where the big holes were supposed to be. The result was piston/cylinder scoring near the exhaust port within the first few minutes of running. Looked like a no-brainer but was actually a gotcha and to this day I wonder where I should have been able to find that info as even the repair manual wasn't detailed enough to note that orientation. Good luck, and that crank definitely needs some TLC.
I might be wrong but... That side play looks excessive. Check the gap tolerances?
They are supposed to be like that, same as the lt250r. The piston keeps it in placr
*place
@@ivanstalmakou715 Worth checking though, right?
Nice summary and coverage of possible issues from the comments. Get that cylinder lifted up with some base gaskets and jetting set properly and it should be good. As far as the cylinder height, there is usually an overall measurment from the mfg to verify how much its been milled. When the bottom of it gets shaved, it lowers it along with all the ports which totally messes up your port timing too. Raising it up will restore that and get you proper head clearance. Piston was probably lightly tapping the head which crushed the ring grooves and caused the piston scuffing.
Bottom end looks great. Looks like piston might be hitting the head gasket. And make sure your ring gap isn't to Small on next piston. Those cranks don't have thrust washers like modern cranks . Have thicker ones same size as bearing
Dang, someone who knows that Suzuki didn't use thrust washers on their big end rod bearings! The piston centers the rod on the crank.
On the same page with you, 2 stroke rebuilder!
Probably need to stick with the junkyard salvage and avoid the performance quads if your not properly checking things and just throwing it together kinda winging it. Tolerances I believe wasn’t checked as everyone else said the first time it blew up.
He doesn't listen to anybody that actually has knowledge I know exactly why it blew up clearance when a piston scuffs on the four corners that is what's called a cold seizure the piston swells up faster than the cylinder can expand this is quite common with forged pistons and steel sleeved cylinders it's not quite as bad in plated cylinders as they can expand faster and you're 100% right he should stick to the junkyard salvage shit because he doesn't have the knowledge to build high performance quads where the very slightest clearance that's too tight and you're done I had a $2,000 Banshee Cub cylinder chip the plating in less than half an hour it was the players fault but shows you that things can happen on even expensive cylinders but he needs to take the quadzilla motor out of it put a Banshee motor back in it sell the quadzilla motor to someone that knows what they're doing and just beyond his way riding the Banshee a good built Banshee motor will put a way more power than a quadzilla motor any day no matter what porting is done to the quadzilla motor
Why dont you make some videos and we'll critique your job
@@mattstewart222 I do this stuff for a living I don't have time to worry about a goddamn camera and angles and editing and all that bullshit it would slow me down way more than the value of the video would ever be worth I can make 10 times as much money in the period of time it would take me to film I can make that money doing work and putting vehicles and ATVs out the door instead of worrying about filming every fucking thing
Try a thicker base gasket, check ring gaps and put more 2 stroke oil in it at least for the run in period.
Great fix on the puller btw👍
Mike Sabo I believe says that people have been know to put bronze bushings between the crank bearings and case's
your right, it is difficult to see from this point of view, I am wondering if the center case gasket surface is good or not. yes, typically an air leak should make the motor idle hight but it is also possible to overcome than but running a larger pilot jet, especially if it is a small leak. I seem to remember that suzuki does not use a center case gasket but uses a special cement to seal that surface. If the motor was ever too hot it is not impossible that the center cases are warped just a little, just enough create a small air leak. good idea to replace the main bearing seals. I am wondering if someone milled either the cylinder to eliminate a warped base gasket surface, not impossible, I had one that did. I ended up dressing it by hand and then I ended up adding more gasket material to compensated for the difference. checking deck height would be important as well.(deck height = top of piston to top of cylinder at TDC Japanese bike typically do not have this issue but you never know who was in this motor before you or just what they were thinking. the other thought i had was that the cylinder was bore out of alignment. but since you had the cylinder done, that is unlikely.
Doing clut h side always pull foot brake lever off, saves a lot of smashed fingers.looks pretty smooth.
Love this series, you never know what will happen in the next episode :)
Just to add to this some manufacturers shim con rods from bottom and some from top. If there is side to side movement at crank end then there should be little to no play at piston.
Still think crank bearing area moving at some point, may feel good and tight but I've seen it happen. 2 strokes are high rpm so they can do some wierd stuff.
Leave suggestion on what you think went wrong with this quad! I will be reading all replies! Thank you!
Here is the piston I used to rebuild the quadzilla. Thinking about going with a different piston next time.
Wiseco piston: amzn.to/33dKXx6
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definitely the con rod too long
Put a new full bottom end in it . Don't take the risk of buddy would had before you shotty work
or you need a stack of base gaskets, don't think the piston should come up above the bore
Perhaps the barrel has been skimmed before due to overheating because of the water leak..... Needs a thicker have gasket.
@2vintage I guess you didn't see my message, I can tell you exactly what happened an why. When you get a cylinder back or even after honing. When you wash it you need to get your hand in there an scrub it clean. Swishing an rinsing won't get the left over from honing an boring. After you wash an scrub the cylinder use a clean paper towel an wipe it. It will leave black on the paper towel so you need to keep cleaning it till you wipe it an there isn't any black being left on the cylinder. If you don't the crud is abrasive left over from the honing an if it's not cleaned well you end up getting stuck rings an scratches. Just as you had happen. One other thing. When you drop a cylinder on you never want to twist it so that it lines up, by turning the cylinder like you did on that assemble causes the rings on one side to have the ring gap forced right against the ring gap center pin an will cause the rings to stick an cause cylinder scratching. I am sure that's the first time you have turned the cylinder like that an probably didn't know that's a no no. So just make sure you get the cylinder clean an check with the paper towel wipe an leave the reed cage an intake boot off when dropping the cylinder on. So it drops down lined up. On the piston smacking the head more time than not it's caused from a missing alignment shim causing the cylinder to be moved forward it back a couple millimeters but it could also be the other owner has the cylinder deck shaved a little. To fix that you just need to use a oem base gasket that has the small bead of black silicone on it, thicker or even doubling up 2 base gaskets to get more thickness. Then might have had the cases decked/ shaved because it had bad scratched or the replace one side of three case an had it done because they didn't line up even. Either way thicker base gasket will fix that. They do make different sizes so you can alter the squish band. Good luck, it's a cool machine I want to see you get it going trouble free.
Only way to know crank seals are new is to replace them. Quite a bit cheaper than a piston. That rid moves quite a bit side to side.
Had a similar situation, was a bent rod. Below up the motor twice before I figured it out.
I’d double check squish. I definitely agree on the thicker head gasket.
Those crank bearings are shot that left one sounds try as hell and you wiggled the crank after splitting the cases and there was play
Inf the rod was bent you would get spiral marks on the piston skirt starting at 90* to the wrist pin. From just below the rings down.
This problem could 100% being avoided had clearances been measured on your end you wouldn't be going through this mess
I wonder if someone machined the sealing surface on the top of the cases. It is a trick to lower the cylinder and reduce transfer and exhaust port duration. Seems odd the bolt boss by the base gasket sealing surface wouldn’t have paint on it. Would result in the piston sticking out too far with a stock rod and piston compression height. I enjoy the channel!
I do not miss those cold ass days! I am from Northern Illinois but now I live in Phoenix, AZ. Was 67° and bright sunshine!
There’s Also a dot on the crank shaft that lines with the counter balancer gear and primary drive gear so there is 3 dots in all
Are the water pump blades right for the direction the water pump turns
I saw that too
Joe use a sharpie and color the head in and put it back on. Cycle the piston up and down a few times and pull the head back off and look for witness marks in the sharpie
The case to cylinder surface has been milled down a lot as you can see at 31:09 where the paint is missing or has been sanded down in the location where the top case bolt goes through.(see the base gasket surface closest to the camera? Beneath that you can see the paint is missing on the case top. You need to compensate for this with either 2 base gaskets or if they sell a thicker gasket.
Pull out the crank and have it rebuilt. This time with thrust washers. Then, and only then, have it correctly balanced. Eric Gorr is in Wisconsin, why would you spend your money any place else. The PO lied to you about the crank or the washers he installed got turned to metallic paste.
The lt500 doesn't have thrust washers on the big end of the rod just smaller thrust washers on the piston pin to align the rod on the crank.
I believe the bottom of the cyl was machined down for the lower port timing or for a repair. If it were me I would get billet thrust washers and the correct wrist pin bearing for the thicker washers and then call cometic and get an array of base gaskets ranging from .020 to .059 to try and get the squish were it should be. Also I'd get a few different head gaskets in various thicknesses and get them for an overbored cylinder. Please put new crank bearing and seals in there while you have it apart.
Have you measured the crank to see if it's a long stroker with a normal piston and head
Thanks to your quality video camera, I can see that the top of the case has been machined.
The lowered cylinder is causing the piston to hit the head. You can notice this best by how close the raised print "... STROKE" is close to the machined surface for the cylinder base.
Before throwing more money at it, check that the connecting rod is truly straight. Easy and free to do. I thought the top looked a little tweaked. Just my 2 cents.
Parts book shows thrust washers either side of the rod on the big end. Not any on yours.
That bolt that you were having a hard time getting off or the nut I should say is reverse thread you're cranking it tighter you have to go the way you would normally tighten it up to loosen it reverse thread
Piston to bore was measured by the guy who did the cylinder, but not the ring end gap. Rings got warm, expanded and bound up on cylinder wall, scoring it, and losing compression
The ring gap was measured by the guy who did the bore job
The thicker base gasket will help. Just one thing though. Make sure the counter balance is matched to the piston. There should be a guide on how to match it at least there is on cars. I've worked on many Honda preludes that have a counter balance similar to what you have. If they are not timed right and if they are not matched to the weight of the pistons and the crank they can destroy pistons, crack piston rings, over stretch the rods,and destroy crank and rod bearings and many more things. I would do some research into it if I were you. It might sound stupid but unfelt vibrations in an engine can cause stupid things to happen. Good luck. Hope you solve the issue.
So all things considered after watching the full vid… I would definitely say the piston is contacting the head just enough after warming up that it is being mushed down against the rings just enough to grab the rings and score the cylinder… I wouldn’t even attempt another start on that engine until you get a bit more clearance between the head.
Check if there is a plus one crank because most people put stroker cranks in 2 smokes to get more power
Hey man I know you might eventually figure this out on your own but if Sabo happens to offer help with this engine you might wanna hear what he has to say 🤷🏼♂️
He is still learning to bud
He won't
@@250race dude both these guys are good but Sabo is better, Sabo tears his engines down to nothing rebuilds it better. This guy he's good but he cuts a LOT of corners attention to the little details is non existent. Buys cheap parts off ebay, if this guy would go the extra mile and do things right he would be awesome. And one more thing I also think if he would get off the floor and work on a table or workbench he could do better. But you can lead a horse to water but you can't make him drink.
There were metal shavings in the crank area I would replace crank bearings n get OEM crank or connected rod kit there should never be any shavings in crank area
@@cheto2952
They both need to start running oem bearing and cranks.
I personally agree with everything your saying dosent sound like it’s sucking air and the crank looks perfect this would stump me too man sucks it’s such a cool machine
The side to side play is completely normal, it’s just for lubrication purposes. I rebuilt one and had the same concerns with the side to side play but it’s all good.
Keep it up, can't wait to see it
running!!
I'm no keyboard warrior and I'm just posting my thoughts. I'd check if the rings are binding all around or just one or two spots, if they're binding all around somethings up with your piston to head clearance, if they're binding in just one or two spots then I would believe using the lead solder wire to check clearance caused the aluminium of the piston to warp and pinch the rings. You can check clearance of the grooves for the rings on the new piston too to check if they're not to tight for the rings you're using.
Check to see if the crank haves are parallel. That will cock the piston weird in the cylinder.
The inside of that engine looks sweet 👌 love the blue I think it looks better than the red and super glossy from the oil
U have a lot of patience Joe. You’ll get it right keep at it
Coukd the crank have been off centered, one way too much to either side and then pushing the piston into the cylinder wall?
the piston is hitting the head still, just enuf to crush down on the rings to make them stick but not enuf to feel when u kick it over.
Maybe try to check cylinder head to piston clearance again. Is it normal for that case to look like it was machined down where the cylinder seats against it? Maybe try a thicker gasket?
Should’ve left it a Yamaha! Not you but the guy b-4 you! Keep up the hard work and determination Brosky
My quadzilla on the factory sticker by the gas cap says to run it at 20:1 gas mixture. New oil probably can go leaner but on a new rebuild I would mix it rich anyway. The worst would be a fouled plug.
The crank bearing sounds rough, i would replace it. Some people are saying you are missing thrust washers on crank, a few are saying there are only smaller thrust washers on piston side of con-rod.
Double up base gasket may get your piston squish correct
Could the rings also be hitting the gasket causing the ring issue? Did u check the gasket for contact marks? At the end of the running vid it seems like it was starting to seize or get tight. Wiesco pistons need a lot of clearance since they are forged and heat up different than the cylinder head..check the cooling system for equal flow around cylinder. Check the power valve operation..
Hard to see clearly but its looks like someone forgot the two washers on each side of the connecting rod(09160-24022) but i wouldn’t think that would cause the piston over travel, i think someone decked the cylinder or head to increase compression and got a little carried away.
Thrust washers not used on some Suzuki cranks, rod is centered in the piston and will not move side to side very far.
@@MM_in_Havasu agreed but if that a stock crank it did have them, that’s the part number I gave him
That crank bearing thing can get spendy fyi. What isee it looks pretty solid but only has to spin a bit to throw rod up . Love watching you work, wish I had 3 of you here, I could actually run my shop and not be busy all the time...
I would add the new crank seals forsure just to be in safe side but man what a beautiful beast to be so close to breathing again
Measure the rod. Make sure it’s not to long. For whatever reason the piston is smacking the head would be the reason the rings are stuck
Smacking the piston to the head has nothing to rings get stuck. This piston is made from poor aluminium grade.
Ok
I think it might have been running too lean and lacked a nice rich run-in session to seat the rings properly. Rapid heat increase with lack of lubrication would expand the rings to maximum tolerances 🤷🏻♂️🤷🏻♂️ always run richer on a fresh engine especially in cold environments 👌
I don’t know if it’s just me but That crank bearing sounds kind of loud! Might want to get the clay out and check your piston to head clearance .also check ring end gap? And totally agree I will put the crank seals in there while you’re there!
Hi Joe i think that the block was decked so a thicker gasket on the base and on the head might work but the block loohs to have been surfaced
Clogged radiator causing overheating? Witch also explains blown pump seal
The next question Fuel mixture. Is is heat and or clearance? Is it jetted to lean? Do you need more 2stroke oil in the mix? Is it drawing air in after the carb? Like a manifold suction leak following the path of least resistance. Is the cooling system working Water pump, Rad and thermostat.
You may want to put some oil on your puller before to use them, this prevent stripping them and keep threads clean
Maybe the connecting rod is out of spec. Like something so small you wouldn't be able to notice by eye. Could be a little too long?
you just need an ali spacer and 2 gaskets. remember dont run piston too close to the head. because as soon as the bottom bearings get any play at all ... boom shes done
either wrong rod. or the barrel has been shaved to much over the years. as you are thinking. you may need to ajust timing a tiny bit for performance.
it will be fine.
Ring gap? Are the rings expanding and causing it and also I don't think there should be side to side movement. Missing washers maybe..??
Hope you get it fixed joe it's a nice quad seeing a lot of comments on washers are missing from the rod causing play in the piston plus thicker head gasket for clearance maybe something to look at mate a lot of good comments on this hopefully that's what the problem is take care and all the best 🔧🔧🔧👍👍
Any update on the progress of the Yamaha banshee/Suzuki 500
You might Look into the shims for the crankshaft big end and small check all tolerances and follow the guide you should be fine
if it's 2 cycle it should run on 50 to 1 that will fix your lube problem. just saying
Holy shit! No smoke is no oil. If oil/fuel is 28:1, which is lots of oil for a 500. Then, way too lean on pilot jet. It's got squish, lots of it. That crank bearing sounded dry 27:05 when you moved it with your hand, while your trans bearings are silent. No oil from too lean on the pilot. it ran on the pilot the entire minute and piston scuff proves no oil. Start with a 50 pilot and let it foul a plug. Main in the 175 range and read the plug before WOT runs or it will squeak every time, if it's lean. It blew up on the road due to lean WOT A/F ratio. It hurt my soul when it squeaked. You can hear it. Been there, squeaked a couple too. Keep going!
The lower end of the connecting rod looks really sloppy (side to side) to me. Not sure what the measurement is suppose to be. That would be something I would check to reassure me. And would be curious on the thickness of the gaskets for the bottom and top of the cylinder since it does looks like the piston is possibly hitting the cylinder head and pinching the rings like you said. I would maybe go as far as reinstalling the "old" connecting rod if it's ok. A lot of money spent for 11 minutes of use so far. I feel for ya.
Look to me like the heads had a skim at some point and a standard top gaskets not thick enough for clearance when hot maybe?
Mmm no thrust washers on big end?the gaps look to much to me?
Is it the right rod? Did you check the model # of the rod? Could be too long which is why it hit the head. I would also make sure that all the bearings are flush with the case.
As everyone else has also said . check clearence to the head . missing thrust washers . but I am surprised noone has metioned the exhaust either. If that has been modified or changed to fit the motor into the banshee frame it may be flowing to much or nlt have enough back pressure. I'm sure you undsrstand how a 2 ztroke works but without that backpressure could cause you to run lean ... I do not think that is the issue with your "squished piston" but something to think about and just surprised noone else mentioned it
use some plastaguage and see how much crush you get on the top of the pistion, maybe u need to add a second base gasket to raise it up a wee bit. Too me the piston and bore dont seem right just by going by the marks it left on the cylinder wall, do u have calipers to measure that and check the clearance? I dont know about these newer bikes but back in the 80's we had some cylinders that could not be bored, maybe thats the case with this jug.
You should consider a Milwaukee 3/8 impact. There amazing 450ft lb of forward torque and 650 breakaway
My kids 2015 yz 450f crank berings had no play but when they got taken out you could shake them and they made alot of noise
Did you install the shims on both sides of the piston when you inserted the wrist pin into the crank rod
i have the same thing happening with my 1998 rm80, no it’s not blowing up but the crank has no washers on the side of the crank which i’d never seen before!!