Redman45 2 #1 Posted July 15, 2017 I have a 1994 520-h with a 20hp onan. The thing is in good shape and the electrical looks to be 99.9% original. The problem engine just cuts out. There is no sputtering or any pattern. If when it cuts out I turn key off then back on the motor will come back up. I've jiggled the key and the key harness while running to attempt to stall motor and this does not effect motor which leads me to believe that key is not the problem. I do not believe this is a short problem because after stalling the motor always starts back up. What do y'all think !?? Share this post Link to post Share on other sites
R. L. Addison 299 #2 Posted July 15, 2017 I would try a new switch. I've seen this before on a couple vehicles, and it cured the malady. 2 Share this post Link to post Share on other sites
Kurt-NEPA 755 #3 Posted July 15, 2017 (edited) I had a similar problem with my 88 520H. If I wiggled the plug on the back side of the ignition switch I could usually keep it going. I replaced the switch and plug and never had any problems again. Welcome to Red Square Edited July 15, 2017 by Kurt-NEPA 2 Share this post Link to post Share on other sites
Redman45 2 #4 Posted July 15, 2017 I appreciate your help and don't mean to second guess but what's going on in the switch that would make this happen? I would think that the key switch is a set of contacts that are eather closed or open ? Like I said I can wiggle the key and the rear key harness to attemp and induce the symptom but that doesn't make the motor quit. Someone said it may be the flywheel sensor causing this issue??? Share this post Link to post Share on other sites
N3PUY 1,031 #5 Posted July 15, 2017 Mine did that also. It was the 9-pin connector to the motor. 1 Share this post Link to post Share on other sites
953 nut 51,029 #6 Posted July 15, 2017 3 hours ago, Redman45 said: don't mean to second guess but what's going on in the switch that would make this happen? I would think that the key switch is a set of contacts that are eather closed or open ? Inside the ignition switch there is a brass disk with a few dimples that is spring loaded. It makes contact with different terminals as it is rotated to different positions. No telling how many times it has been manipulated, but things cane wear out. Share this post Link to post Share on other sites
Redman45 2 #7 Posted July 16, 2017 That sounds very plausible ! I will give it a shot and report back asap. Thanks !! Thanks 🙏🏻 Share this post Link to post Share on other sites
96WS6TA 37 #8 Posted July 16, 2017 Hey guy. I'll sell you a nice 1997 520 for $1300 and a smack in the mouth Share this post Link to post Share on other sites
R. L. Addison 299 #10 Posted July 16, 2017 My experience when I autopsy bad switches regardless of symptoms, is that the charging system, feeding back through the switch, overloads the terminal, it gets hot, and burns the contacts inside, they melt the plastic or in some instances the heat collapses the springs, and sometimes even burns into the terminal disc allowing intermittant contact, thus causing frustration and foul thoughts. Share this post Link to post Share on other sites
Redman45 2 #11 Posted July 22, 2017 OK guys my good buddy ordered me the switch because he's an ok guy. I put in the new ignition switch and the tractor is still doing the same thing. What do ya think?? Share this post Link to post Share on other sites
Redman45 2 #12 Posted July 22, 2017 Hey n3puy you say it was the 9 pin connector ? Were your symptoms exactly what I described in my first post ? I think that could be a possibility but the only reason I don't feel it is an electrical issue of that sort is because the tractor always starts back up . I've also shuck the connector while the tractor was running and that didn't cause it to stall. Just curious what your symptoms were ?? Share this post Link to post Share on other sites
N3PUY 1,031 #13 Posted July 22, 2017 YEP! It would just shut off as if I had turned the key off. But it would start right back up. One time it was dying I was quick enough to grab that harness and it kept running. No problem since I cleaned and resized the female terminals. I still have the new connector on the shelf. Share this post Link to post Share on other sites
Redman45 2 #14 Posted September 13, 2017 OK guys the 520 H is up and running !!!!here's what was up. I replaced the key switch as recommended then replaced all three relays... no go. I then replaced the refractor and then also replaced the capacitor..nope! Cleaned a bunch of wires and connectors ...na.Then I took the advise of my good bud 96WS6TA because he's a decant guy at best .. to replace the ignition trigger. So we pulled the flywheel and discovered that the stater was filthy dirty covered with dust ..we proceeded to clean that all up replace the ignition trigger started it up and BLAMO !! That's it !!!!!!!!!!!! He even gave me the part to ! What a guy!! So we let it run for the longest it's ran since I've owned it and she didn't shut down. then a new problem revealed itself . The 30 amp fuse begin to melt. I pulled the wires out of the fuse block and made a joint because the fuse connection was poor creating a high heat connection . Probably wasn't a problem before because I wasn't getting great voltage off of the charging system because of it being so dirty. Just wanted to let you all know in the hopes that it might help someone else along the way and thank everybody else for their help also thanks to my good buddy! 2 Share this post Link to post Share on other sites