# crankshaft 1995 polaris 250 trail boss



## car 54 (Oct 17, 2009)

can some one tell me how to get the crankshaft apart to put a new rod on it i tried polaris dealers and machine shops they don`t know how. thanks for any help and advice


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## FABMAN (Dec 18, 2008)

New crank is best, but its pressed in. # 7 presses out but I think it will need to be set up to be pined first, and by the time you have it pined and balanced you'll have enough money in to it to pay for the new crank with a new rod on it. A good independent shop is best to take it to or an engine builder.


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## car 54 (Oct 17, 2009)

thanks for the information. if i buy a crank assembly its 373 dollars plus shipping i`ve already bought a rod kit for 52 dollars. surely a machine shop wouldn`t charge near that much(300) to set up a jig to press that pin out and install the new one and check alignment.


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## FABMAN (Dec 18, 2008)

Well if it takes 3hr they will and they need to drill it to put pins in it sideways so it lines up and stays there then balance it.


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## car 54 (Oct 17, 2009)

i guess i will use the old one as is .i want to order the piston for it machine shop said .020 would clear the bore up but i want to be sure and order .040 is there any advantage to staying small on a air cooled engine


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## FABMAN (Dec 18, 2008)

Yes you'll get more re-bores out of it before it needs to be re-sleeve and if you think the hole crank is spendy you don't want to go there. If they say all you need is .020 go with it. If they need more you can return the piston for a bigger one or have them order the piston then it there problum if its wrong! Thats what I do. But they usually know what they are doing. If your looking for more power spend your money elsewhere like clutching, exh pipe, and carb. You don't get that much out of boring a 2-stroke.


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## car 54 (Oct 17, 2009)

well, i bought this polaris new in 1995 for my daughter i have never had any problems with it until either the oil injector pump gear broke (it`s plastic ) and broke the piston or the piston broke and caused the gear to break. i don`t need a hot rod all i need is something to putt putt my 3 year old grand daughter around the yard.the machine shop is 45 miles away.he didn`t look that close at that cylinder. i have to pay for gas and shipping


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## FABMAN (Dec 18, 2008)

Are you going to fix the pump or start mixing your gas? They do make a block off plate for the pump.


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## car 54 (Oct 17, 2009)

i`ve already bought a new gear (steel ).i have all new gaskets and seals. so what`s your advice on the .040 piston ?.if it blows again i`ll buy a engine off e bay


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## FABMAN (Dec 18, 2008)

Well it sounds like you made up your mind already. As far as time looking at the cyl all they need to figure out what to bore it to is mic the bore (1 or 2 minutes at most and that's including finding the tool) to measure it then they go in there books to see what size pistons they to offer if they don't already know. In 
your case they have STD, 0.020, 0.040, 0.060, 0.080 from Wiseco.


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