So I've replaced the entire ignition system... 2 coils and 2 trigger coils... Stator,cdi, Another flywheel... Different crankshaft.(the crankshaft finally gave me nice blue spark) Crank seals, oil pump o-ring. top end gaskets twice... Piston 050 over jug bored accordingly. Compression is 120, I'm getting fuel and spark. I've isolated the ignition system from anything that might affect it. Nothing only a small pop once in a while. I've tried gas and ether in the plug hole with no results.

 

120 psi on a new top end is still kinda low. Even so with new crank seals should at least run on ether. Gotta have good compression, spark, fuel and air.If the stator plate is where it was originally,timing should be good. If it's off, could be part of the problem. If you're sure on the ignition timing, have. a good fuel supply,then you could do a leak down test to at least eliminate an engine case, head/ base gasket, lower end leak. If it can hold 7 psi with no leaking then think you need to go back to the top end.

 

Thanks for the quick reply!! The original stator had only 1 mark I could find but it didn't seem to correspond with anything so when I removed it I noted that it was about in the center of the slots I put the new one ( which has no marks) in roughly the same spot as the old one. ( I've also tried moving it several times with no results). For the leakdown.. I've yet to get some fittings. What all is involved with it? I put 50+ lbs in the spark plug hole and it's all I can do to keep it from spinning the engine over. I also put 50+ lbs in the crankcase by way of the drain. I have to have the piston up and cover the carb boot to build pressure. Is this right? Doesn't seem to be leaking anywhere ( at least by listening) i can put pressure in until my hand is no longer sufficient over the carb boot. I'm also concerned about the compression. I have checked for broken rings and they are fine. Ring gaps face the intake side. Just seems like it should do SOMETHING with a shot of ether down the plug hole. I've tried going back to the original ignition system with no difference in spark or results.
This was a perfectly running machine till it quit on me one day. Managed to get it re started but wouldn't idle. Got home and had feeble orange spark. Started chasing ignition till there wasn't anything left. Finally checked compression and found the top end was bad. New piston time! Still wouldn't run, feeble orange spark. Noticed the flywheel would wobble and figured that was my spark issue. Had the crank trued and was told it was OK, nothing wrong. I wasn't convinced because i had to beat it to remove the flywheel the first time after breaking several puller bolts. So new crank, seals and all that good stuff. That got me blue spark finally and I thought I had it made but no still the same results I've always had.

 

This is a 2 stroke not a 4 stroke! Can't take that much pressure.. Beyond 7 psi you take a chance on blowing out crank seals.. Think that's what you need to check now. Especially the one behind the drive clutch.

 

Will do! One forum said to check with 100 psi which seemed like way too much. During the whole time I had the pressure in there it never leaked out anywhere that I can tell so I doubt I blew it out. Never hurts to check though.

 

OK so i stopped and grabbed enough stuff to hopefully do a proper leakdown test. Any tips on doing it correctly besides the 7 lbs? We are wanting to put 7 lbs in and it should maintain that pressure correct?

 

Several ways to do this. You can block off intake and exhaust ports and pump air in the plug hole or just block off exhaust,leave the plug in and pump air through the intake. Yes it must hold 7 psi with no leak down. Spray soapy water around the case,head and base gaskets to check for any bubbles. Several videos on this on YouTube.

 

OK, i made blank rubber gaskets and blocked exhaust and intake. Then plumbed it so I could use an air chuck to add air in the plug hole. Now I can check it with a tire gauge. Went in and ate supper then checked again. Still just a little over 7 lbs.

 

Then one of a couple things that i can think ofif fuel supply isn't a problem. Either timing is still off or the 120 psi is just too low on a new top end When i bored cylinders and installed them I could get at least 135 psi on average or a tad more.. Either one of these can cause it to not run and just pop even when you give it a shot of ether.

 

OK so when I removed the original flywheel the very first time, I heated it and one of the magnets fell out. I jb welded it back in so I could try it. It didn't work so I got a used one with matching numbers. I just now saw an old thread about reverse polarity on the magnets. I checked my flywheels and sure enough they are backwards. I stuck my old jb welded one back in and boom fired right up. Idles nice and everything! A whole year chasing my tail because of that.. .. Had I done a top end to begin with and never touched the other stuff it probably would have been fine. Oh well, at least the motor should be solid. Just need to find the right flywheel now... Thanks for all the advice OPT!!