MMRanch wrote on 07/06/10 at 05:48:01: I doin't think there is a person on this site that doesn't want to see and hear REX go. Lancer what kinda of stuff is REX doing? If I understand right ... Rex has a oversize dome piston , a high long cam , a long intake manifold with a rich carb on the end of it , and has lost a lot of weight . Is that close ?
piston...yep
cam....yep
intake....yep
weight....yep
carb &/or carbs .... crazy stuff going on
I found what I thought was THE problem, but it was not all of it.
The intake tube from carb to head was made from pvc which was ok until I removed too much material in the effort to get a better fit and when tightening the clamp the pvc cracked which made for a huge air leak...see photo .....................
so I reverted to the VM carb which now has a metal carb-to-head tube which will not crack, but there is still sililar symptoms.
It will start, with some difficulty at times;will rev pretty good most of the time but will cut out periodically; and will cough/sputter back through the carb.
My thoughts about a bent valve or cam chain jumping the sprocket are that the symptoms would be more regular, instead of the on & off nature they are now.
What do you think ?
Would a valve or jumped chain cause the erratic symptoms ?
I really do not want to have to remove the head cover again.