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Discussion Starter #1
I bought an old sled with low miles (200) that sat for years. It was not a big investment and I was testing the waters to see if I wanted to get in to sledding. I siphoned out the old gas as best I could changed plugs and oils and went sledding. The third ride of the season the engine just cut out. My local shop (HK Hookset NH) did the diagnosis. One cylinder has low compression likely overheated piston. They blamed the old gas and dirty/clogged carbs. They suggested a completed tear down which would cost over $1,500. The mechanic mentioned I might get by with new piston and boring out the cylinder but they were not allowed to do that at the dealer. Anyone have experience with the second option. I'm wondering what a ball park figure might be for labor and parts.
 

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If the bottom end is ok, you should be able to do the top end with general hand tools and without pulling the engine. You will need a torque wrench to put the head and base nuts on the cylinder back on. A repair manual is also helpful.

You won't know the cost until you have the cylinder off. Sometimes they can be honed to remove any slight scoring. If that cylinder has nikasil-lined cylinders, those are not able to be bored unless the shop has specific boring tools that can deal with the nikasil.

Once you get it apart and it's damaged, you can send it to Millenium Technologies or US Chrome and they can repair it to like new condition. Send them a piston/rings and they will fit the piston to the cylinder, which saves you a step. The price for repair will be about half that of buying a new cylinder.

Then figure out the issue as to why it burned down. If it's the left (Power Take Off PTO) side, the seal on that side may be bad, which allows air to enter the crankcase and leans out the mix. Check the carb boot adapters and make sure the carbs are SPOTLESS. If you don't, you take the chance of burning lean and having to do it all over again.

The Fan engines are pretty simple, there are lots of stories of folks that burned a piston and removed/replaced the piston/cylinder while on the trail. The lack of antifreeze is great for that.
 

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Welcome
Don't be afraid of opening up a 2 stroke engine
I have said a long time ago a piston cost about as much as a full tank of fuel!
Actually they run about $50 ea now.
 

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Discussion Starter #4
The sled had companion sleds that were brought to the dealer at the same time. I had them go over the running ones. I was told all the carbs were full of crap which likely led to the lean out on the one I was riding and the failure. This is good info. I will do some reserach on the cylinder material and cost of replacement vs repair. Nice to know the pistons are so cheap. Any recommendations on a decent brand to look at?
 

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Not Wisco but I use SPI when I've had to do rebuilds on friends snowmobiles. Thankfully I have never had one go boom...Knock on Wood! Also the place KC mentioned will sell pistons as will Indy Specialities they will match up the pistons to the cylinders you send in also.
 

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I'm wary of Wiseco as well, even though I have used them on two engines over the years with good results. You really have to set them up to Wiseco specs exactly to make them last. Wiseco's are a forged piston (dense) so the piston expands faster than the cylinder (cast) which can result in a cold seize if you are not warmed up completely.

I've used SPI's as well and have never had any issues with them, either. That would probably be the brand I would get if it were mine...
 

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Same here, Wiseco are just too finicky. I've used them on dirt bikes and quads in the past but with SPI making really good pistons/rings these days and for half the cost as well. I'd rather go SPI vs Wiseco all day long.
 

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You have to remember that Polaris or whom ever, did NOT make their pistons!
So saying a OEM piston can be bought Way cheaper than the 300 percent mark up!
Absolutly no issue with repairing a gouged cyl boreing or replateing!
Polaris just wants you to buy their cyl @ $300-400?
 

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Once you get it repaired try to stay away from the ethanol fuel. Out here you can get all 3 grades without ethanol. (Sinclair) and that's all I will put into my smaller engines.
 

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Yes but that isn't like that everywhere. Only place to get ethanol free is premium and they charge at least a dollar more here if not 1.25-150 more a gallon. At those prices I will just use 87 and clean the carburetors every preseason that doesn't cost me anything but a couple hours to do vs almost doubling my gas cost.

But yeah I get your point here with no ethanol fuel. If they would sell it at the same price or even .10-25 cents more it would be a worthwhile option here in Wisconsin but it won't happen because Midwest and Corn sales.
 

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Discussion Starter #12
OK will stay away from Wiseco and get the piston at the same time as the cylinder repair, very helpful

Thanks
 

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Discussion Starter #13
Researching pistons I found Sportline SP1 and Wiseco any others? The Wiseco are expensive. Do you need to replace the control arms as well? I wouldn't think so but was wondering.
 
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