Forest Road 594 #1 Posted February 13, 2012 I'm looking at a 416H with 600 - 700 hours. Owner says it will start and after 15 minutes gets hot and shuts down. He thinks the stator cracked and heats up. When the stator expands it looses spark. Sounds kinda fooey to me. ANy thoughts? Valve seats? The price is right with a deck and plow. Still I'd prefer ea running machine. All thoughts, comments, ball breaking is welcome. Thanks!!! Share this post Link to post Share on other sites
MalMac 1,332 #2 Posted February 13, 2012 Well there most certainly is more knowledgeable than I on here that know about onans. My first thought would be check your coil. More often than not on any motor when a coil goes bad they work till they get warm than start causing all kinds of problems. On the Onans it could be a number of things. I do know this, when a Onan is running it's a great motor but when they have problems they are a PITA. A very Very expensive motor to work on. Hopefully someone will chime in on here that can help alot more than I. I have two 520's and have asked alot of questions on here with a lot of help coming from these fine folks. Share this post Link to post Share on other sites
Forest Road 594 #3 Posted February 13, 2012 Thank you. Owner claims to have replaced the coil and fuel pump. He even purchased a shop manual. He doesn't really seem to know whats wrong. Share this post Link to post Share on other sites
AMC RULES 37,196 #4 Posted February 13, 2012 Sounds like you should be able to pick it up really cheap then? :beer: Share this post Link to post Share on other sites
Hydro 131 #5 Posted February 13, 2012 I'm not a mechanic but if you are having valve seat issues which this does not sound like and I say that only because I had a 416 that developed a valve seat problem, do a compression test. In my case one cylinder had no compression..ZERO... the other 60 lb and it started and would run but just on one cylinder. At first I thought it was electrical but was I ever wrong. If you have to rebuild an Onan..up here $2000.00-$2200.00 and I'm not so sure it's that much cheaper in the US. :twocents-02cents: Share this post Link to post Share on other sites
Forest Road 594 #6 Posted February 13, 2012 I'm not a mechanic but if you are having valve seat issues which this does not sound like and I say that only because I had a 416 that developed a valve seat problem, do a compression test. In my case one cylinder had no compression..ZERO... the other 60 lb and it started and would run but just on one cylinder. At first I thought it was electrical but was I ever wrong. If you have to rebuild an Onan..up here $2000.00-$2200.00 and I'm not so sure it's that much cheaper in the US. No rebuild here!!! At this price it'll become a parts tractor. Share this post Link to post Share on other sites
Hydro 131 #7 Posted February 14, 2012 Sounds like you should be able to pick it up really cheap then? I can tell you if you are looking to drive your 2 stage with the Onan, it will do the job Share this post Link to post Share on other sites
TT-(Moderator) 1,162 #8 Posted February 14, 2012 I would lean more toward the ignition "trigger" module mounted under the flywheel. I've never had one go bad, but have read plenty about the "shuts off when hot" syndrome and it's usually the trigger that's to blame. Share this post Link to post Share on other sites
546cowboy 302 #9 Posted February 14, 2012 I have had that problem with more than one Onan and you will find it is the ignition trigger module. It is under the flywheel an replace it with a new one. I put a used one on once and two months later I had to tear it down and do it again. If I remember right that new one was about $80. Share this post Link to post Share on other sites
Forest Road 594 #10 Posted February 14, 2012 The owner is pretty sure thats the problem. He refers to it a the stator. So ill be pulling the flywheel if I by this one. Thanks guys! Share this post Link to post Share on other sites
Hydro 131 #11 Posted February 15, 2012 Do the compression test too, out of an abundance of caution! Share this post Link to post Share on other sites
BOWTIE 226 #12 Posted February 15, 2012 HELLO, WHEN IT RUNS AND WARMS UP BEFORE IT SHUTS OFF ON IT'S OWN. CHECK TO SEE IF BOTH CYLINDERS ARE HOT. IF NOT IT'S HAS A DEAD CYLINDER. THE COMPRESSION TEST IS THE BEST WAY. THE CYLINDER HEAT TEST IS SIMPLE WITHOUT TEST GAUGE. GOOD LUCK BOWTIE IN OHIO Share this post Link to post Share on other sites
