Hello, I have a 150cc Chinese quad engine that uses a gy6 engine. It's been burning oil real bad, so I've done several things to try to fix it. I have changed all the gaskets in the top end. I also replaced the valve assembly with new valve seals, as well as a new piston with piston rings. After putting these new parts in, my four wheeler still burns oil pretty bad. I have used a 10W-30 and a 10W-40 oil, both burn in the engine. When I did a compression test before the new parts, it read 150psi. After the new parts, it read only 70psi, so I put a tiny amount of oil through the spark plug, and got 125psi. I decided to start the engine, and it ran for several minutes until I turned it off. It burned oil for most of it, then stopped. I would hit the gas and no oil would burn. I started the engine again a couple of days latter, and it kept on burning oil, even 10 minutes after I started it. Could a fuel additive like Lucas oil stabilizer work in a gy6 engine? I don't think I have any other options beside this, but maybe you guys have ran into this as well.

Thanks,
-Quad nerd

 

Check the breather system. Single cylinder engine breathers work far harder than most multi cylinder breathers. The only places oil can get into cylinder to burn is the head gasket, valve seals, piston rings, or breather. Assuming you have not messed up when fitting the others, the breather is all that is left.