400ex trouble! help

[polakmike7]

2001 400ex..jus replaced top end after the quad was running like ****..burning oil..cutting out etc. new top end is in now and it started for about 2 mins same symptoms and now it wont even start...is it compression? or bottome end?

help me out im all outta ideas

[ae13291]

give us more info, could also be the rings, but you should let the valve seals and all that seal in by running the engine, check the spark plug and make sure there is oil in the motor

[John451]

When it cranks over does it go blub blub blub blub or vrooooooooo? If it's the second one then it would be compression.. While the plug is out if it looks good plug it back into the boot and put it on the cylinder head near the plug hole and crank it over and seee eif it sparks. keep us posted with the results.