Gary S Minnesota 52 #1 Posted April 2, 2023 Not to beat the subject to death, but it seems I see an unusual number of longevity/durability references on the Onans. Frequent mentions of valve seat and connecting rod issues on the Onan P220 in particular. Comments recommending the importance of the oil filter gasket and maintaining clean cooling fins are common. That being said, does anyone have a 520 H with 1500, 1800 or 2000 plus hours that continues to run strong?? Is the Onan P216 also AS susceptible to rear cylinder issues? I have 1 of each (1070 hrs on the P220 , no hour meter on the P216) and hope with careful maintenance they will run for many more hours? Your experiences? Thanks 1 Share this post Link to post Share on other sites
cleat 6,007 #2 Posted April 2, 2023 I have only gotten one Onan powered machine with a working hour meter so I can't say how many hours they really have. I would assume most of them had a lot of hours based on wear of other components. Never had one lose a seat and currently have 5 520's that all run great and have bought and sold a few 416's that all ran great as well. I bought a 416 with a bad engine that had the seat so hammered that I could not find an engine shop that could fix it. I got that one really cheap and it has been a great parts machine. I know that does not answer your question but the 520's are now around 30 years old so if one was going to come apart I would think it would have done it by now. Share this post Link to post Share on other sites
WHX?? 48,823 #3 Posted April 2, 2023 (edited) I have had 5 of them. Two have 1800 hrs on them and still run strong. One had 600 hrs on it and had severely ovaled bores and got parted out. Never a problem with valve seats but all my belt guards are ventilated. All have/had issues with the nine pin. I believe they would all see 2k hours with proper maintenance and regular oil changes. No doubt PO lack of love was the issue with the ovaled bores. Cooling fins plugged tight not to mention plugged hydros and sludge in the oil pan. Everything I have seen boiled down to lack of maintenance. Onans did not do well to "run it like you stole it". Edited April 2, 2023 by WHX?? 2 Share this post Link to post Share on other sites
kpinnc 12,067 #4 Posted April 3, 2023 My 520-H has about 800 hours, so it may not meet the requirements of this thread. But- I have a Toro Groundsmaster that sat for nearly 10 years with over 2500 hours before I got it. I mowed with it for another 5 years (hourmeter stopped working) and still have it. It still runs like a top. Needless to say, the stories of 3000+ hours on a well maintained Onan Performer are absolutely true. I hope yours gives you decades of service. They are great when we take care of them! Share this post Link to post Share on other sites
victorb 46 #5 Posted April 3, 2023 My `94 520H has 1430hrs and was running fine when I put it away for the winter. 1 Share this post Link to post Share on other sites
RED-Z06 2,221 #6 Posted April 16, 2023 Its so hit and miss, ive seen P220s go 2000hrs using nearly no oil...and seen them eat a seat at 400. Share this post Link to post Share on other sites