I just got a 86 350 fourtrax , ran fine yesterday, trailered it home, now wont start.
It is getting fuel, and spark. Check valves, and adjusted to factory specs, but still not starting. Any help would be great, Thanks, Jim

 

I think thats the year with the fuel pump since the tank's lower then the carb. You may need a new one, but alot of people have had success adding a primer button from a skidoo to pump fuel up to teh carb for starting. Once the engine is running it will suck fuel pump or no pump.

 

The fuel pump is kicking fuel to the carb. We have looked and looked, and it appears to be the compression. Order a new piston, and I'll keep evryone posted. Jim