Sled is a 2010 RMK 800 with 500 miles.
Piston photo - what do you guys think?
- Thread starter go high fast
- Start date
Looks like photo loaded upside down.pistons are stock original OEM.
V
volcano buster
Well-known member
Looks cracked to me too.
I would pull the top end off and really check it over. Too easy for it to grenade.
local Polaris dealer recommends updating to Polaris Pro pistons. Does this sound like good advice or bad advice??
Yes that piston has a horizontal crack in the skirt, it needs replaced. I would measure the cylinder also to see if the bore size is correct. Check the clearance with new piston also.
I would look into installing one of the poo fix kit? Do a little research on here as there is lots of good info on them... I've had good luck with Mtn Techs kit..
anybody have experience with the Bikeman Fix Kit? Looks like the only difference compared to the MTNTEK kit is the Wossner piston vs. the Wiseco piston?
I agree, first order of biz is to inspect and mic out cylinders to make sure i don't have other more serious problems. Then i think I will do "fix kit". Plan on keeping the sled for a long time. FU Polaris for not having this figured out by your engineering department by the time 2010 rolled around.
Been a Polaris guy all my life starting with my '96 XCR SP but next time I am in the market for a new sled if Suzuki still makes motors for AC I may stop by the AC dealer for a peek. Just ridiculous. Where is Fuji when you need them.
I agree, first order of biz is to inspect and mic out cylinders to make sure i don't have other more serious problems. Then i think I will do "fix kit". Plan on keeping the sled for a long time. FU Polaris for not having this figured out by your engineering department by the time 2010 rolled around.
Been a Polaris guy all my life starting with my '96 XCR SP but next time I am in the market for a new sled if Suzuki still makes motors for AC I may stop by the AC dealer for a peek. Just ridiculous. Where is Fuji when you need them.
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Got a little wind back in my sails. After a marathon wrestling match with the airbox and lots of profanity I finally have the head pulled off and looking from the top both pistons and cylinders appear to be in excellent condition. Will bring it to the local Polaris dealer to have them miced and then go with the fix kit and hopefully never look back. Also adding the SLP airhorn kit with full pipe system and high elevation head at this time. Will keep you all posted.
Most nervous about pulling the old Pistons and installing the new ones. This is a job I have never done before. Any tips are appreciated.
By the way, whatever happened to piston wash?
Thanks for all the help.
Most nervous about pulling the old Pistons and installing the new ones. This is a job I have never done before. Any tips are appreciated.
By the way, whatever happened to piston wash?
Thanks for all the help.
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Hey GHF, sorry I missed what everyone is saying is a crack when you emailed me those pics. I would still wipe the piston clean once the top end is off but while you are in there I would definitely do a "fix kit". Mtntek is pricier but they are probably worth it. Spacer / gaskets / taller pistons.
When you need a hand give me a shout, I just did the top end on my 860 and know all some tricks to make it easier / safer (wrist pin clips into the crankcase are a bugger). I can swing by after work if you run into anything that you need a hand on. Also, have Polaris run a hone through the cylinders to put some new fresh scratches in it. I did my own with my own hone but I would actually prefer normally to have the shop do it, their hone technique is usually better.
Sorry I have been so obsessed with finding my own no-start problem I did not even ask how your sled project was doing! When you are done it will be solid as a rock.
When you need a hand give me a shout, I just did the top end on my 860 and know all some tricks to make it easier / safer (wrist pin clips into the crankcase are a bugger). I can swing by after work if you run into anything that you need a hand on. Also, have Polaris run a hone through the cylinders to put some new fresh scratches in it. I did my own with my own hone but I would actually prefer normally to have the shop do it, their hone technique is usually better.
Sorry I have been so obsessed with finding my own no-start problem I did not even ask how your sled project was doing! When you are done it will be solid as a rock.
F
Flatlander44
Member
Just had the exact same thing. Lots of damage when I actually pulled the engine apart. Me and a very reputable engine builder tore the engine apart. Found lots of scoring on the cylinder wall, and the piston was f-ed. Piston looked like all the oil was washed off or it wasn't getting oil. We talked to a polaris engineer and sent pics. The concensus seems to be clogged fuel filter and lean burn down or oil reservoir with clogged vent in the oil cap and lack oil. I rebuilt the engine with 2 new cylinders, and long rod kit. Also drilled a hole in the oil cap. Also installed a new fuel filter and as overkill, new injectors. The polaris engineer said a small restriction in the fuel filter can be a major issue. He also told me to think about premix the gas. 100:1 but the EPA does not approve of this and he can't recommend this. Just took the rebuilt motor around the block for break in. Hope I'm good. I'll try and post results
no problem sledhed.
The good news is that the snow conditions are so horrible that we are not missing much of anything. By the time we solve our mechanical gremlins I'm hoping we have a couple of major blizzards and our spring riding season in March, April and May will be legendary just like all years past.
I think I have decided to go with the fix kit from Bikeman. In the meantime, I have adjusted the track on the ZX and greased its thoroughly today. May have to call on her one or two more times.
I will let you know when I am ready for the Piston swap. Right now I am making a little bit of progress each day at the pace of an amoeba but so far all appears to be on track just fine.
Good luck on the no start problem. That is one heck of the mystery. When Chris is not around I recommend lots of profanity as it seemed to work for me on the airbox removal problem.
The good news is that the snow conditions are so horrible that we are not missing much of anything. By the time we solve our mechanical gremlins I'm hoping we have a couple of major blizzards and our spring riding season in March, April and May will be legendary just like all years past.
I think I have decided to go with the fix kit from Bikeman. In the meantime, I have adjusted the track on the ZX and greased its thoroughly today. May have to call on her one or two more times.
I will let you know when I am ready for the Piston swap. Right now I am making a little bit of progress each day at the pace of an amoeba but so far all appears to be on track just fine.
Good luck on the no start problem. That is one heck of the mystery. When Chris is not around I recommend lots of profanity as it seemed to work for me on the airbox removal problem.
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