Today I had the needle & seat replaced in the Mikuni Carb of my 500. The problem I had was gasoline leaking out of the drain line below the carb while the engine was running. The service department told me that it was simply worn out and had to be replaced. At the bottom of the needle is a small rubber stop which is what was worn down to where it could no longer control the flow of fuel properly. I have 55 hours and 250 miles on the machine. Has anybody else experienced such wear with low hours and low mileage? The service department said it was nothing serious and that it was just normal wear. Wow. For $113, I sure hope I don't have to spend that every 250 miles, but who knows. I guess quality in some things are not what I expected. BTW, the dealership told me this is not a polaris mfg. issue as the carb is not made by them. I do love my 500, but this was definately a surprise to me.

 

Just hopped on over to the polarisindustries.com website and found this under technical:

Understanding the different carburetor circuits will help you to maintain your ATV for best performance. The Inlet Needle and Seat control the float height, which will affect fuel flow at all throttle positions. Whenever fuel flows from the float bowl overflow tube, or fills the engine when the unit is not being used, test or replace the needle and seat. These components can wear out and will need regular inspection and maintenance.

Yep, that's exactly what my problem was. Again, is 250 miles and 55 hours seem like normal wear? I'm sure it depend on how one rides, but I don't race and most of my riding is under 30 mph.

 

If you replace the needle and seat yourself it is $33.Takes about an hour to do.