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Discussion Starter #1 (Edited)
So i bought this sled a while back and i knew right from the get go i was in for work (becuase it sat for 5 years and only started once) but not like this. i changed the gas, oil, changed the lines topped of the cool juice and checked all the plugs, wires for spark all three have them and i no that because i used one of those electricity testers or whatever that looks like a screw driver with a long neg wire any ways i think its only runnin on one cylinder well i no for sure to tell you the truth but i dont no why, its getting gas because that plug is always soaked and the other 2 bone dry, when i switch the plugs same shit, soaked plug other 2 dry. the cylynder thats not workin in the left. i also noticed coolent on top of the spark plug hole but then realized it was dripping from the coolent cap right on top of the motor or am i just sayin that to make my self feel better? so tonight i went for a little ride and it ran great agian but on my way home when i stopped at a stop sign it wanted to die it revs at 2000rpm but at the stop sign it was about 1000. i've been reading other forums but i just want a straight answer at first i though it wasnt firing so i read and came to the conclusion it might be a piston sleeve, then i read about the coolant leak adn that lead to the headgasket, but why does it run so good untill it gets warm expecially today? i mean as long as i keep the rpms above 4000 its great but under that no power at all. the only mod is a racing clutch so i've been told and 120 studs. help would be greatly apprecialted thanks guys.
Brad
 

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already did all that..is there any ways it was my crankshaft bearings? because now the motors stuck.. you can stick a wrench on the primary and turn it but it sounds like a load of scraping and grinding. it doesnt seem like its my pistons becuase once i free up the motor and start it it runs perfect untill i give it some throttle and as soon as the rpms drops back down the motor just stops a dead stop with the track and the secondary still spinning. todays im takin apart the bottom end anyways and ill tell you guys what i see. thanks for the reply please continue to help
 

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Do a compression test; if you dont have a tester you can buy a basic one for like 20 bones at any large tool store. Each cylinder should have at least 120 psi in order to function properly. If you are leaking coolant, you need a gasket kit. Once you are replacing the gaskets you can inspect each piston and sleeve for wear. Lastly you should make sure the carbs are in-sync "not the band", and adjust the idle so you are sitting about 1,500 rpm.
 

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Discussion Starter #6
hey i just tor the motor right down and found the culprate witch was a broken crankshaft bearing..split right in half almost right on the groove on the bearing. so does anyone no why that would happen its on the clutch side 2nd bearing in. i checked the pistons, rings, and cylinder walls for scratches n stuff and saw nothing perfectly smooth same with the pistons but the piston that was right above the broken crankshaft bearing was brand new looking when i took it apart while the other 2 were jet black on the top why was the other one new looking? and would this explain lack of power and why its not hittin its power band and possibly the reason why its runnin on 2 cylinders? sorry i got so many questions this is my first sled, first sled motor tear down and i wanna do it right i might as well pick up some good habbits while im young. thanks guys. and does anyone have the specs on this sled? like the torque specs for the motor? and about the idleing. it idles a 2000 steady kicks in at 4000 right on but i cant get the rpms past 7300ish..no matter what even downhill i mean this thing should be able to stand with 120 studs right? plus the rebuilt clutch?
 

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Discussion Starter #8
so how much would that cost me? i mean i was only lookin for a season outa this sled then upgradin to a newer one next season..i mean by no damage done to the inside it is mint..even this older guy who was helpin me out couldnt belive how clean it was inside. it almost sounds like im screwed for this engine by the stuff i've read and the things i've been told...
 
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