520h Electrical trouble

[HunterdonNJ 1]

Here's my story.... My 416h blew the back exhaust valve seat so pulled it aside for a winter project. Find a 520h for sale locally and bought it. Not in great shape but motor and hydraulics are dry and works well. Mow two times and then it won't start. Read here about the fuse block and other electrical problems so run a wire from the switch to the starter and add rewiring to the winter list. After two mowing's I now have to start it, shut it down and turn the key back on quickly to shut the starter from continuing to run. I changed the switch and didn't fix. I really cant have a lot of down time as I have too much grass to mow. I'd hate to buy a third mower as I'm low on space. Any thoughts for a quick fix, short term of course?

 

TIA

Jonas

[cleat 4,936]

Could it be the start or switch relay sticking.

 

Try swapping the 3 relays located between the engine and battery support around (they just pull out) and see if anything changes.

 

 

[WVHillbilly520H 10,369]

Check all your safety/interlock switches my most recent 520 sat outside most of its life the actuators on the PTO and/or Clutch/Neutral micro switches could be missing that was the issue I ran into while getting this one ready to now this past month,P.O. had jumpered the starter to the ignition switch bypassing the broken neutral switch instead of replacing the culprit of a no start issue, essentially the switch was good but wasn't working without the missing actuator,Jeff.

[squonk 38,844]

Those little micro switches are known for crapping out especially around damp enviroments. 

[HunterdonNJ 1]

That brings up another question. I gather the switch can be bad even though your not getting the blinking signal on the dash? As nothing is blinking except for oil pressure and normally if a switch isn't activated it does.

 

Thanks much

[WVHillbilly520H 10,369]

Just take a moment and look at my pics 1st one as I was taking it apart to clean and get a general idea of how bad things may be I didn't even notice the actuator was missing then about 2 weeks in to it all circuits "checked" out but for the life of me I couldn't figure out why it wouldn't start without the jumper wire from switch to starter solenoid, finally after getting frustrated one day I had the wire off then pushed the pin in on the microswitch and it attempted to turn over, looked that part up online and sure enough the actuator was missing so I replaced it and all it fine for now...my point is always check the simple things first fuses switches connections ect then worry about replacing parts...you say you replaced the ignition switch be very careful because although they look and fit the same some of those just don't work with the TORO/ONAN combo or with electronic spark ignition vs points/magneto ignition some of the posts aren't in the correct orientation could be causing your continuous starter running issues,Jeff.

[WVHillbilly520H 10,369]

Just take a moment and look at my pics 1st one as I was taking it apart to clean and get a general idea of how bad things may be I didn't even notice the actuator was missing then about 2 weeks in to it all circuits "checked" out but for the life of me I couldn't figure out why it wouldn't start without the jumper wire from switch to starter solenoid, finally after getting frustrated one day I had the wire off then pushed the pin in on the microswitch and it attempted to turn over, looked that part up online and sure enough the actuator was missing so I replaced it and all it fine for now...my point is always check the simple things first fuses switches connections ect then worry about replacing parts...you say you replaced the ignition switch be very careful because although they look and fit the same some of those just don't work with the TORO/ONAN combo or with electronic spark ignition vs points/magneto ignition some of the posts aren't in the correct orientation could be causing your continuous starter running issues,Jeff.