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Power valve wear?

Summerizing sled and noticed a bit of oil residue / leak around the power valves. Popped them off to clean up. In the process noticed some fine filings on the cloth from both guillotine ports. Cannot see any obvious scoring on either piston / rings / power valves but plan to check with scope in the am to confirm cylinder walls and bottoms of cylinders as best as possible without disassembly....
Sled was running fine prior to fogging.

In the meantime, do the valves tend to show wear?

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Aluminum .... scoped both cylinders this morning through exhaust ports, plug holes and valve and couldn't see anything of concern on pistons or walls ...

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Odd, I've had the brass bushings wear out at approx 4500 km. If you are high milage, possibly worn through the bushings and into the body of the ex valve bar.
 
Tks - Will have a closer look at the valve assembly before going further ...not high miles mostly tree riding ...

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Looks more like brass when hit with a bit of cleaner against a dark rag....
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Definitely some slop in the guillotine bushings ...put it back together checked compression 125 psi on both cylinders at sea level throttle bodies closed with no pipe / muffler attached ...same as start of season ...
Will order new base plate to compare ....

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My 2016 had filings and were worn out at 2500 kms. Warranty replaced them. I hope the 850's don't suffer from this.
 
I just replaced the base plate on my 16 with 3500 miles on it after having oil blowing out past the seals for half the season and brass shavings... make sure you loctite the guillotine bolts when you put it back together
 
We just did my son's 18 800 163 AXYS power valves as a result of a cable failure. The PIA removal due to the steering post removal was the only problem (Thanks to Polaris foresight). We did look at the bushing wear and found minimal wear at 2200 miles. Put the guillotines and assembly into carb cleaner over night and washed with warm water and clean assembly re installed with new cable -- to the dealer for relearn and to the mountain with no problems, hope to get a few more rides yet this spring as there is still over 70 inches of spring snow here and under 25 degrees for the last 3 days and down to 1* two nights ago here in town. I plan to do my 18 AXYS this next fall before next season at 1600 miles and is will take a careful look at the cable while I have it down and if questionable I will replace it then!
gtwitch in wyoming
 
Gtwitch, FYI
I have done this numerous times, I just remove the front steering tie rod end, then the bushing in the lower steering post, as it will move out of the way enough.
As you pull the exhaust valves out, just pull the valves in the full open position with a finger and rotate the assembly up and out. Fast and simple, same when installing them.
 
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