What does shiming do?

 

Shims are use in setting specific clearance between the valve lifter buckets and the cam lobes.If a valve is too tight the cam is removed,a smaller shim inserted under the lifter which increases clearance,the cam is bolted back down and clearance is checked again. May take a couple times and different size shims to gain the correct clearance range. Same thing if the valve clearance is too much. A larger shim than the one that is installed is used decreasing the clearance,cam is bolted back down and clearance is checked again. Shims are numbered according to size.After all 4 valves are within specs,the cams are timed at tdc,the chain is reinstalled along with the tensioner. This can be a labor intensive job best left to someone that has done this before.

 

how much do you think it would cost for polaris store todo it?

 

Valve adjustment is usually about the price you'd pay for the box of shims or maybe a tad more from most dealers.. Some things it's best to let the dealer invest in such as all the shims,specialty tools,unless you plan on doing the work your self and keeping the machine awhile. No sense on buying certain tools/hardware if you may only use it once.One of those damned if you do,damned if you don't type situations. Even though most of you hate dealers on the forum,at times they're a necessary evil as you may say when it comes to certain repairs.

 

what kind of feeler guage would i want for this?

 

Clearance is .006 (.15mm) on the two intake valves. .010 (.27mm) on the exhaust valves. Standard auto feeler gauge. If you don't have a manual here's a pdf service manual for 5 bucks that shows what's involved if the valves are out of adjustment. Can help you decide if you want to buy the shims,do this service or let someone else service it if needed. Polaris Predator 500 service manual repair 2003-2007 - Download Man...