i removed the rear plastics and gas tank to gain access to the motor so i could clean it up a lil to see if there were any leaks anywhere i used break cleaner since it dosent leave any residue and is non flamable i got a good portion of it clean before running out of spray after letting it sit for about 30 minuits i put everything back together an it started fine an ran for a second then died now it will start but wont idle it runs fine if you give it a lil gas but it will die if you stop. and ever since ive owned it the motor shakes alot at low rpms is this normal in the belt housing it looks like the pully has rubbed the back of the case

 

chances are the clutch cover is warped(alot of the older ones did) causing it to rub and will evently rub a hole through it unless it already has. i don't think excessive shaking is normal on low rpms. if it was idling fine it should be some what smooth w/ good throttle response. i'm assuming this is a 400 and did you change the oil in the harmonic balancer and make there is no leakage in or out. just a thought.

 

Rear engine to frame mounts behind the clutch backing plate were prone to separating and causing engine vibration,movement, and would cause wear to the belt and warping the rear cover along with the exhisting problem of the early outer covers distorting. Just grab the engine and see if you can move it any at the bottom. Best if you have the clutches and backing plate off then you can tell pretty quickly.The 400 only has three engine mounts(front,one at the top, and one left rear). As far as not idling,sounds like you may have some trash in the carb. OPT

 

stendori you assume corectly its a 96 400 4x4 i forgot to put that in there lol. i changed the counterbalancer oil today and it barely had any in it i had less than 50ccs including the lil shot of seafoam i poured through it to clear out any debris im gonna try and get the carb out an cleaned tomorow an see what happens and i get alot of mixed answers about what type of oil to use in the rear tranny ive heard anywhere from 5w30 to 85w140 thats a big diffrence to be wrong something from the parts store would be ideal since the closest dealership is far thanks for the help i cant seem to find a manual that covers this perticular model that they dont want $200 for

 

Polaris AGL for the transmission OR oil recommended for chain driven gear cases(usually available at most auto stores) DON'T put thick oil like 80/90 or 85/140 in the transmission!! Counter balancer calls for 30wt oil OR any multi wt oil such as 10/30, 10/40. Holds only 75cc's oil! OPT

 

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