Engine Cannot stay running, easy to turn engine with clutch in
- Thread starter userix
- Start date
Absolutely! Although the cylinder and quite possibly the piston are now junk. 
Take care to find exactly what caused the damage and if you choose to rebuild the top end, be doubly sure that there is no debris in the lower end from this damage.
I still find it strange that you could not hear the piston traveling in the cylinder though. Even with poor compression caused by the gouge you found, it still should have made some put-put sounds.
Take care to find exactly what caused the damage and if you choose to rebuild the top end, be doubly sure that there is no debris in the lower end from this damage.
I still find it strange that you could not hear the piston traveling in the cylinder though. Even with poor compression caused by the gouge you found, it still should have made some put-put sounds.
Man, this is my second brand new engine; it died a pretty fast death, just after I about finished breaking in the engine and was enjoying some 32mph cruising speeds Upon closer inspection, there was another vertical gouge on one of the side ports and both piston rings snapped in one place. There's also gouges on the sides of the piston head itself! The wrist pin holes on both sides of the piston head got altered so much, I had to dremel it bigger just to be able to remove the piston. The top of the piston has more craters than the moon. I have no idea how that much crap could have gotten into the chamber. The foam air filter of the stock NT carb is still intact, albeit heavily oil-soaked. It's pretty gruesome to say the least lulz.
What exactly do you mean by the "put put" sound? Isn't that the normal engine noise? What exactly does piston travel sound like? It did get noticeably louder, but it still seem to run fine before its death knell.
Spraying carb cleaner around a leaky gasket will cause the engine to rev higher?
Don't get me wrong, when they do work, it's loads of fun cruising around for hours.
Upon closer inspection, there was another vertical gouge on one of the side ports and both piston rings snapped in one place. There's also gouges on the sides of the piston head itself! The wrist pin holes on both sides of the piston head got altered so much, I had to dremel it bigger just to be able to remove the piston. The top of the piston has more craters than the moon. I have no idea how that much crap could have gotten into the chamber. The foam air filter of the stock NT carb is still intact, albeit heavily oil-soaked. It's pretty gruesome to say the least lulz.What exactly do you mean by the "put put" sound? Isn't that the normal engine noise? What exactly does piston travel sound like? It did get noticeably louder, but it still seem to run fine before its death knell.
Spraying carb cleaner around a leaky gasket will cause the engine to rev higher?
Haha, my bad. It's frustrating how much bad luck I have with these engines. When it's not the bike frame snapping on me, it's either the gas tank leaking from studs or the engine cannibalizing itself from the inside out.
Don't get me wrong, when they do work, it's loads of fun cruising around for hours.
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My bad on the "put-put". I got 2 threads mixed up in in my head.
Try a 4 stroke build. They seem to be much friendlier and have a much, much longer lifespan.
That's the way I am going with my next build anyways....
Try a 4 stroke build. They seem to be much friendlier and have a much, much longer lifespan.
That's the way I am going with my next build anyways....
Yup - quick and easy way to test gaskets and seals. Many other shop aerosols will work as well, but carb cleaner is safe for your engine.
Weird, in my case, when I spray carb cleaner around the gasket, the engine dies, not revs up. Is that indicative of another problem?
Not another problem, it just indicated that you have a leak.
When spraying flammable stuff around gaskets to check for leaks the result of finding a leak will not always be an increase in engine speed, although usually it is. Sometimes it will be a reduction. If it is really bad it can stall the engine due to too rich of a mixture being introduced into the combustion chamber.
When spraying flammable stuff around gaskets to check for leaks the result of finding a leak will not always be an increase in engine speed, although usually it is. Sometimes it will be a reduction. If it is really bad it can stall the engine due to too rich of a mixture being introduced into the combustion chamber.
Interesting - every leak I've ever had causes the engine to race (rev up/increase RPM). I'll have to remember that a stalling symptom would indicate the same thing [a leak].