crazy passworD 3 #1 Posted June 21, 2021 i have a onan p220g with 1100 hours . The pressure on one piston is 75 the other is 80.The tractor is a 1990 year. It smokes a little on start up,but dosent burn a lot of oil. Question is it time for new rings or should i wait. crazy rassworD Share this post Link to post Share on other sites
Handy Don 14,061 #2 Posted June 21, 2021 How many hours do you run it per year? How many years do you want it to last? From your description, if you intend to keep this machine for more than a year or two and have it retain its value and usefulness, then it is time for a good look inside. It may be as simple as rings but it may be more--valves, valve seats, and the bores all need to be checked out. The bonus is that after being put right, it'll have more power and stop smoking! Share this post Link to post Share on other sites
lynnmor 7,815 #3 Posted June 23, 2021 It may only need the valves freshened up along with new intake valve seals. I don't lap valves, instead I properly grind them and then cut the valve seats followed by cuts to get the seat width correct. Pretty much all Onans will give a puff of smoke on startup. Share this post Link to post Share on other sites
