[pumpkintruck]

i purchaced a 2001 500 rubicon from my father-in-law, it is in good shape, but it smoked really bad. i spend my pastime fixing, rebuilding & restoring snowmobiles, atv's & cars. i figured "hey how hard can it be to fix this problem". i have bored the cylinder, replaced the piston assy. & reasembled the engine. i have checked with a few honda dealers & have found out there is a ring land breakage problem on the oil ring, (this was the problem when my in-laws tried to fix it, but i have checked my work and my piston is fine.) is there some problem that i have missed, i have run the machine about 60 minutes since the last rebuild, smokes awful when cold, not as bad when hot, no noticeable blow-by, am out of ideas. this machine has kicked my butt, and will probably be on ebay in pieces soon if noone can help. my honda dealer has the same machine with the same problem, they can't fix thiers either. if i could figure it out i will probably own that one too.(i can buy it cheap) HELP PLEASE

 

[TRX2fiveO]

Valve Seals and guides perhaps?

 

[pumpkintruck]

valve seals & guides

i'm sorry i left that bit out of my story. new valve seals & the guides felt very good. company i work for has full machine shop. thank you very much for the response, i really need it!

 

[450RMAN]

Ok i need u to try something, i had this happen one time. Take the exaust off of it all of it leave nothing comeing out of the cylinder, i had a atv that would leak oil onto the top of the piston when u left it not running, the oil would then be pushed into the exaust when u started it and would smoke horribly untill it burned it all off, even tho i couldent find anything wrong with my head, after i changed it it stoped, but that was on an old suzuki it might not be the same

 

[TRX2fiveO]

I would say that like Josh stated may happen but I would bolt on another exhaust system if the core of a muffler becomes saturated with oil it will never burn out. I have seen this alot on small engines. I almost forgot about that.

 

[jeeping1974]

have you done a compression and leak down test on the motor before and after the rebuild? With what you have done in the past, i'm sure that you did nothing wrong, just wondering what the results are.

Changing the exhaust like Moose said might help/fix the issue.

Did you check for flatness on the motor and head? Maybe if they overheated at one point, one surface could have warped just enough to cause a small oil leak. Just a thought though.