SgtBob 27 #1 Posted May 5, 2011 :thumbs: I recently bought a 1993 520H tractor with 360 hours on the meter. This thing runs great for about 5 min. then dies and will not restart for a couple hours. In checking with a local shop the mechanic said it sounds like the coils needs to be replaced. Does this sound right ?? If so does anyone have a used one for sale, or is this something I should buy Share this post Link to post Share on other sites
Shuboxlover 474 #2 Posted May 5, 2011 I am pretty sure I have a used one for you, the tractor had 1050 hours on it before the valve seat decided to do it's little dance. I don't know if the coil was ever replaced. Do some research and let me know if you are interested. Share this post Link to post Share on other sites
tunahead72 2,346 #3 Posted May 5, 2011 Don't know much about coils, but there's a similar stalling problem over in the "Wheel Horse Tractors" section, may give you some ideas: http://www.wheelhorseforum.com/index.php?showtopic=27818 Share this post Link to post Share on other sites
yamahalic63 0 #4 Posted May 5, 2011 Could be the ignition module, try this link: http://www.perr.com/phpBB3/viewtopic.php?f=14&t=3248&start=0 Share this post Link to post Share on other sites
300zx 7 #5 Posted May 5, 2011 Bob, the Onan coils I have had that either failed open on the primary side (small terminals) or secondary (spark plug wire holes). I haven't had one that got weak with heat. To really know if you have a problem with the coil, the next time it quits, check the resistance across the small terminals and then across the two plug wire holes. It should measure around 3.7 ohms/17,000 ohms respectively. Check it cold also. If the resistance isn't breaking down, then I would think the coil is good and you have another problem. John Share this post Link to post Share on other sites
