:cussing: HELP PLEASE!! -

sorry about re-posting this, i had it in the polaris forum but got no replys

POLARIS EDGE X 800 FRIED, would like to know how water in the gas, and/or
not letting a sled warm up long enough can cause problems. Here are the pics, do you think the cylinder is re-lineable? I was running on year-old gas when this happened. Also the so-called 'good' piston has 2 burn marks right above where each ring closes on the piston, is this bad/normal? Any ideas, explanations would be greatly appreciated and helpful, thanks.

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Too lean, Detonation, Coolant leak, Or crank bearing cage parts that flew thru the engine...

a lean condition caused detonation and broke the ringland letting rings loose to beat everything to death. the year old fuel didn't help the cause.
the "burn" marks on your "good" piston you are referring to is called piston wash and is indicating you were too lean.
looks asthough you ran it a long time before tear down to investigate.
Big Bummer!!!
good luck, rob

sounds right, thanks for the info... it was definately all top end so it wasn't anything with the crank bearing cage and if this helps - the plugs were a really light gray - also the guy driving it did ride for a while after he was having trouble with it and even drove 50mph on one cylinder, dumb ### should have stopped when he was having trouble, do you think i should replace the 'good' piston while i'm at it?

Really Light Gray plug is another lean condition indication.
replacing both pistons is a good idea, if it's scuffed or alot of miles.
look at the piston crown edge on the exhaust port side of the piston for "melting"or pitting indications. would highly recommend honing and new rings at least. 2 new piston assemblies with new wrist pins and wrist pin bearings would be as good as it gets.
be sure to pull crankcase out of sled and flush it out to remove the debris. you'd hate to do all other work to have debris take out your lower connecting rod bearing or crankshaft bearings.
hope this helps, best to do it Right to have "peace in mind" when out on remote trail by yourself. rob

Hey thanks a lot - only 2400 miles on sled, the 'good' piston has no flaking, pitting, or melting, i'm sure i'll probly replace it anyway, can I hone with the nikasil coating? what do you guys think about the bad jug, is it repairable at all?

is there anything i should look at that may have caused the lean condition, other than the water in the gas? i really don't want that to happen again thanks

Check your carbs...if gas sat in it for a year then a partially obstructed jet may have caused the lean condition. Make sure you are jetted for the temp and altitude your riding...riding in colder temps or lower altitude than it's jetted for would also cause the lean out.

I'm not framiliar with Nik coating but you might be able to re-sleeve it.

Good Luck.

your welcome,
now you'll have a good spare piston. and yes you can hone the good cylinder.
i woud send the bad cylinder off to, US Chrome for repair and renikasil,
US Chrome, 920-922-5066, they recieved federal awards for there outstanding work and there plating hardness.
get rid of that old gas, clean carbs, lower the c-clip on needles 1 position and fatten up main jet by 2 to 3 sizes, example, if runnin 400 go to 420 or 430 to prevent this from happening again until you find your SAFE baseline.
i don't believe water caused this issue. just lean main jetting(lean topend) or needle position(lean midrange).
look for dark tan plugs and piston wash 3 to 4 times the size that your good piston wash is indicating.
if your using syn oil use a standard mineral base for breakin, so rings will seat in, on first tank of gas.
good luck, rob

Did you split the crank case? Did you check the crank seals? Cylinder base gaskets ok ? Old gas with dryed up octane may have caused major pinging but unlikely. Jim