Snowmobile Forum banner

78 Everest 340 loss of power

1K views 3 replies 3 participants last post by  shimsl 
#1 ·
Hey guys, picked up a 78 Everest 340, starts and runs great but as soon as the throttle is more than halfway it bogs almost to a stop. I made sure the carb is clean, and everything adjusted properly, put in new condensers and points and adjusted everything and checked it twice, new plugs, wires, coils... can't seem to shake the problem, compression test was 90 psi in pto cyl and 120 psi in mag side cyl. Not sure if that's enough to cause this much of an issue.
 
#2 ·
you might go over to DooTalk.com and ask them on there. There are a lot more old-sled owners there.
 
#3 ·
You are in need of a top end refresh at the very least.
That wide of a spread between the cylinders compression is the issue.
You are getting too much "blow by" in the PTO side as the rpms increase.
You are also likely in need of a new crank seal on that side.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top