If the compression is low more than likely you have a valve timeing problem or a valve is hanging up from something???

 

that woudl suck that raptor engine is a PAIN IN THE BUTT!!!!!!!!i do not wanna take it out again

 

You do know the engine doesn't have to come out of the frame, don't you?

My opinon is about the same as everybody else's. Check timing, clean the carbs, and check for spark and you should find something there to help you.

 

whoa wait a second i dont have to pull it out of the frame??/ how do you pull that off????? yea we got spark .. i dont htink it is timing because we did have it running *barley* for about 20 seconds but ill check compression 2morrow

 

Everything you mentioned is in the top end. The head and cylinder will both come off without removing the motor. Just the plastic and gas tank need to come off.

Do you know how to check the cam timing? Its not too terribly difficult if you can find TDC, but you do have to pull the cam cover to do it.


Did you adjust the valves whenever you put it back together?

 

yes because they needed to be replaced.. so we took the whole engine out of the frame took the top off replaced the piston and rings and replaced all the valves and adjusted them according the the raptor service manual and put it back in the frame *pain in the ****** but if the timing is off we dont need to take it out we can juss dink with it while its in the frame huh?

 

no i dont know how to check cam timing... my dad did that im assuming he put it in there according to the book

 

No there is no need to pull it out of the frame for what you did or are going to do.

The cam timing is one of the easier things to get wrong during reassembly. As long as he followed the manual it should be ok.


Good luck tommorrow.

 

I don't know, I think it would have to be more than one tooth. I had enough slack in the chain to equal almost a tooth and it ran well. Maybe in the opposite direction it might not though.

 

It could be the decompression actuator is 180 degrees out too, but if you didn't take that apart when you did the rest of the work it's probably allright.