hate to post this here...Arctic Cat question

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on1_wheel

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sorry to ask this question on here but its a general engine question, just happens to be an arctic cat sled in hand...

so my father in law had a burnt a hole on his PTO side piston last weekend, (trying to keep up with me...??? )i offered to fix his sled for him, a 1990 EXT 530 twin

tore down the motor completely but haven't found the cause of the burn down yet, but what i did find is somewhere along the way he bought a used cylinder off someone, turns out he didn't notice but its a re-sleeved cast iron cylinder, and OEM for that sled is nikasil-chrome plated..so we got one good nikasil cylinder (MAG) and a cast iron re-sleeved cylinder (PTO).., both are std. bore for that sled (72mm)

so it s the re-sleeved cylinder that leaned out..

question 1) can you run a re-sleeved and a nikasil together on the same engine??

question 2) would you have to jet the re-sleeved richer (thinking due to poorer heat transfer it wouldn't be able to run as lean a mixture as a nikasil cylinder)

question 3) i can't get a second OEM cylinder but I can get a second re-sleeved cylinder, can I run the same pistons in a resleeved cylinder as a nikasil cylinder, or do i have to re-order new pistons for iron sleeved cylinders??

any help on repairing this engine for him would be greatly appreciated
 
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not sure but i think u can make more power from a nikasil cylinder ..i think it cool down easier ... but piston will melt at same temperature so i guess if u melt it again u must have a air leak somewhere that make the engine run leaner .....make sure crank seal are good ..and carb boot and carb are clean
 
just completely tore it down mod, new seals, gonna have new gaskets everywhere, gonna have new reeds also (those were cracked as well)..we put brand new boots on before the season also...just wondering if its taboo to use mismatched sleeves like this??
 
How long has he been running it like that?? I think it will be fine, just need to make sure to warm up properly as cast iron sleeve will expand slower than piston from cold start, once warm you will be fine. If it were mine i would bore the sleeve .010 over or whatever it takes to clean it up, get correct piston for bore & run it. Maybe try to balance piston weights. How much $ do you want to put into a 1990 sled. Let me back up, If it was mine i would probably part it out to be honest, or light it on fire!!
 
lol...he's pretty partial to his old cat...the cylinder's don't need to be bored, like i said, its all ready to go...my mistake to, its a chrome plated cylinder, not nikasil...

the story i got was he blew a piston about 8 yrs ago, the cylinder needed replacing so he bought this used one off some guy, put it back together with the piston in backwards, it didn't run right, pulled it back apart and put the piston in the other way, still never ran right so he parked it...i don't think he put in a new base gasket (not the best mechanic this guy)

anyway, 8 yrs later i discover this sled behind his shed, pull it into the garage, clean his carbs, change some fuel lines...etc, get it running but it has a bog on low end, runs it like that for half a tank of gas then blows it up..

i originally thought crankseals, but they actually looked good, has new ones now anyway, i actually think I'm gonna put it back together for him with the cylinders that we have but jet him a little richer and keep a close eye on the plugs,...it did run not too badly with exception of the low end bog which i attribute to cracked reeds
 
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