[email protected] 4 Posted November 11, 2021 I did a complete rebuild on my foreman 500 fm 08 and it ran fine for awhile new jug rings Piston crank the works with complete head rebuild then it started smoking bad after about 10 seconds running and burning oil I think it's rings but would like any info guys please Share this post Link to post Share on other sites
AKATV 691 Posted November 11, 2021 Welcome to the forum! If its smoking then I would imagine its either your rings or valve seals Did you overbore the cylinder and put in oversize piston and rings? Did you replace valve stem seals? Also, was it smoking pretty bad before you did the rebuild? If so, you might have oil in your exhaust that needs to burn off still I have seen that a few times after doing piston/head rebuilds, smoked for awhile then went away after it burned off 3 Share this post Link to post Share on other sites
jeepwm69 6,618 Posted November 12, 2021 What he said. Watch your oil level and see if it’s dropping. 1 Share this post Link to post Share on other sites
[email protected] 4 Posted November 12, 2021 14 hours ago, AKATV said: Welcome to the forum! If its smoking then I would imagine its either your rings or valve seals Did you overbore the cylinder and put in oversize piston and rings? Did you replace valve stem seals? Also, was it smoking pretty bad before you did the rebuild? If so, you might have oil in your exhaust that needs to burn off still I have seen that a few times after doing piston/head rebuilds, smoked for awhile then went away after it burned off I put in new standard bore jug and new Piston and completely rebuild head new seals valves and springs I think we found the problem bad oil rings aftermarket that was supposed to be OEM we put new OEM rings back in yesterday and so far it's running good I knew about the oil in muffler ruled that out there was no damage to the jug but rehoned it anyway so new rings will seat . What is your opinion did we miss anything and did we do right thank you very much for your response 2 Share this post Link to post Share on other sites
jeepwm69 6,618 Posted November 12, 2021 I’ve had rings that didn’t seat initially before, and new rings/quick rehone fixed the problem. Make sure you’re using conventional oil and not synthetic to break in a new top end. Synthetic can be too slick for the rings to seat. I use Rotella T4 for break in and then switch to synthetic 3 Share this post Link to post Share on other sites
AKATV 691 Posted November 12, 2021 Sounds like you might have pinched an oil ring or just had a bad/ or undersized set. Glad you got it all sorted out 1 Share this post Link to post Share on other sites
[email protected] 4 Posted November 13, 2021 Yes I think I did and it's got gen 4 Honda oil when I change after break-in I'll put synthetic back thanks for your help guys 2 Share this post Link to post Share on other sites
