Bought this 2001 ranger 500 Nov 11 2013 and haven't ridden it yet. Keeps blowing carb off intake while cranking. Does this about every third or fourth time you crank it. Runs good when it does crank. Been in 2 shops, 1 was a Polaris dealer. No one can fix it. Have to many $$$$ in it to junk it. Have thrown a lot of new parts at it. Can anyone help me? Thanks.

 

If its backfiring into the intake. I would pull the cover and check the camshafts.

 

Cam is like new. Thanks

 

The only other thing I can think of is if it jumped timing. Which I doubt since it runs good when it does crank. Just wondering if it has a decompression ball or whatever Polaris uses is sticking or releasing before it should. Wish I knew more to help. Best advice I could offer would be to ask OPT in the "Ask an Expert" section of the Polaris section of the site.

 

Wonder if the intake valve is not seating properly and during the compression stroke it releases pressure outward through the carb. I would think the head is the issue since a worn cam would just limit the opening of the valves. Check the intake valve spring and valve guide too.

 

pull the exhaust off and try it. I've heard of a partially clogged muffler causing this problem before.

 

If I remember correctly I think he did shear a flywheel key and jumped timing causing the problem.