Davidbrianlove 0 #1 Posted May 8, 2012 I am currently down to one Wheel Horse (a 312-8), and am looking to purchase a backup/second tractor. I have had two Onan-16 tractors (a 416-8 and a 416H), and neither of them made it to 800 hours before they popped a valve seat. The 312-8 is almost to 1800 hours with one rebuild at 1200 hours. I am currently looking at a 416-8 (Onan P216) and a 314-8 (Kohler M14). My past experience, while undoubtedly some of my fault not keeping the the cooling fins on the head clean), makes me think the 314-8 is going to be more durable and more tolerant of the dusty/dirty acreage I mow/till/plow. The 416-8 is a cheaper price, and a much shorter haul if I buy it. If you had to assemble some critical care instructions how to make the Onan engine more durable, what would you recommend? Would it be better or worse to remove some of the shroud around the head that accumulates clippings and dust? Just curious what your thoughts are - I pile up the hours mowing 3-4 acres a week, and putting in gardens, pumpkin patches, etc. I also do snow plow and snow blowing... Thanks for your thoughts. Dave Share this post Link to post Share on other sites
otrelwood 32 #2 Posted May 8, 2012 a lot of guys are drilling the belt guard to the rear of the pulley to get better airflow thru the back cylinder 1 Share this post Link to post Share on other sites
dbartlett1958 96 #3 Posted May 9, 2012 I would keep the tinwork in place as it directs the cooling air to the proper places. That said, I would occaisionally remove it to blow things out and make sure the cooling passages are clean. I would and have done a belt guard modification to vent the area around the rear cylinder head. After having done so, I notice a lot of warm air coming past my right leg while mowing, etc. And lastly, the regular cylinder head checks for carbon and valve adjustments. I run 1 ounce of TC-W3 2-cycle oil in every 5 gallons of gas in every 4 cycle engine I own. Cars, van, mower, etc. The additives help keep things cleaned out, and the extra lubrication cannot hurt. At 500 to 1 ratio, it does not affect plug fouling, or other issues. Share this post Link to post Share on other sites
Davidbrianlove 0 #4 Posted May 9, 2012 Thanks for the feedback - both replies were the kind of info I was looking for. Dave Share this post Link to post Share on other sites
Foozerush 40 #5 Posted May 11, 2012 I have a 416-8 and love the power and sound of it.... Just maintain it and use it.... I think next spring I'm gonna rebuild it just for my peace of mind, my hour meter is stuck on 114 hours it, who knows how many hours it has on it.... Not every onan is a lemon.... Just the ones who didn't get proper maintance.... But mechanical failures do happen.... Jump on that 416!!! fooze Share this post Link to post Share on other sites
WH520 17 #6 Posted May 11, 2012 My 518H is knocking on the door of 1300 hours and still running strong. I always blow the motor and transaxle off thoroughly with the air compressor after I'm done using it for the day to get the grass and dust out of the cooling fins and other nooks and crannies.I also change the oil/filter every 20 hours. I put roughly 10 hours a week mowing on it. I gave my 520H to my dad when his box store tractor bit the dust until he could get something else....it's been a while, I don't expect to see it at my house again It has 1100 hours on it and doesn't use any oil and runs great. Share this post Link to post Share on other sites
Hydro 130 #7 Posted May 12, 2012 I had a 416 H in immaculate condition. I looked after it including using a leaf blower to keep it clean and pressure washed it 2-3 times a season. I cut an acre and a half for four years. I bought the tractor with 300 Hours and it was excellent. It popped a valve seat at 450 hours and this engine was well maintained. I honestly believe the belt guard is a huge issue and seriously obstructs cooling of the rear cylinder which is almost always the one to go. "Hodge 71" a member here has a 416H with over 1400 hours on it and it runs like a charm...go figure but heat is a killer for these engines. Share this post Link to post Share on other sites
JackC 616 #8 Posted May 19, 2012 I have a 1990 416H that I purchased with 1,000 hours and a broken rod on the back cylinder. When I took the heads off I found a lot of carbon caked on the valves but the seats looked fine. It may be that engines produced over a certain period have the valve seat problem due to manufacturing tolerance issues over that period of time. It may also be a heat build up problem for the back cylinder on wheel horse tractors. The location of the oil filter may block some air flow for the back cylinder. Maybe installing a remote filter oil would improve air flow and reduce the risk? I wonder if any studies have been done? Share this post Link to post Share on other sites
