crossfire gy6 will not start
 

Hello, It seems I have worked on the crossfire 150r more than my son has used it. When we first purchased it it smoked really bad and had electrical issues. Last year I changed the piston and rings which fixed the smoking issue and then I fixed the electrical issue with some parts and securing better grounds. It ran and started perfect. By the end of last summer it was getting very hard to start, and when it did, it died with a little gas. This spring I cleaned the carb., check the spark ( nice and blue) flushed the gas tank with new filter and gas. Still will not start. Had to buy a compression tester. Checked it... Only 60lbs. Ok, what happen to my new rings??? Put oil in the head and it went up to 120lbs. Has to be bad rings... again??? Took head and cylinder off, everything looked fine. No scratches or cracks. Honed and then put a new set of rings on (aligned them correctly). The end gap on the new rings was about .010. Should be within specs. Timed and torqued everything down and still will not start. Set the valve lash at .004 each. Checked the compression again and same readings with new rings. 60 lbs. and 120 lbs with oil. I put air into the spark plug hole and noted no air coming out of the exhaust or carb. I thought the oil trick was for the rings, not warped head or valves. Also, when I was trying to start it for the last time I had the oil dip stick out and it sprayed oil out. Is that normal? Never had the dipstick out and tried starting it when it ran. Is that telling me too much cylinder blow by? Valves look ok, so... Bad cylinder-piston-rings-head-compression tester or mechanic? Just wanted some advice before I wasted more money on the cart. Help!

I think it may be possible you may have a sticking valve. maybe warped.

Any other suggestions? Should I just but a complete top end rebuild. Head, cylinder, piston?

Double check your timing. It is often set improperly. Also, when you cleaned the carb, did you remove the pilot jet to clean it? It has a very small hole that requires the jet to be removed to clean it. You could add a small amount of fuel to the combustion chamber by removing the spark plug and usng something similar to a turkey baster to squirt it into the cylinder.if it fires, you will know that fuel delivery is the problem.

It may be if you reused your cylinder before, the cylinder may be worn now.

just curious where did you get your engine parts from? I have 2 crossfires myself, with the Howhit engine.

I purchased some of the parts from http://www.gy6150enginepartswholesale.com/, but not all.

looks like a good site

how did you know which parts would fit your crossfire though?

How Can timing be off. Top dead center is top dead center. Setting the valves when both cam lobes are down.

There are many ways for it to be off. Only one way for it to be right. one tooth off, two teeth off, etc. etc.