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Horsing tuff

Electrical problem 520H Onan

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Horsing tuff

Please help me figure out a wiring issue on a 520h, 20hp Onan. I had a problem at the 30 amp fuse. It melted the wire in the fuse block. I repaired it and cleaned the ground wires by the PTO levever.  It then started fine. I power washed the tractor to semi- restore it, cleaned it up. Now it won't start again. I have checked all of the safety switches but I am completely lost when it comes to wiring. The engine will turn over if I jump the light blue wire across to the red wire on the starter selinoid. I also can not find and actuate wiring diagram for the tractor. The one I have the wire colors don't jive. I also don't know what this is on the top of my Onan engine where these wires are plugging into. Can anyone please help!!!!

 

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DougC

Your last pic. is the voltage regulator for the tractors charging system.

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Horsing tuff

Thanks Doug C. That doesn't have anything to do with it not starting does it? Also on every safety switch their is 3 wires coming out of them. Can anyone help on which ones I need to jump to bypass the switch?

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squonk

A lot of Ca Ca in there. Take the wires apart 1 at a time and clean everything. Another way to do it would be get some wire marker numbers like electrical contractors use. Draw pics of the components and give each terminal a number and put that number on the wires with the marker number

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lynnmor

When you power washed (never do that!), you might have messed up one of the three relays below the battery.  They are common relays and can be found at most auto supply stores.  They can be found real cheap at various online sites.

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gwest_ca

There is a link to a set of detailed wiring diagrams here

Each circuit has it's own diagram making it easier to understand.

 

Garry

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Horsing tuff

sucsess !!!!..... I feel so stupid, I waited until the last thing to check the main ground wire from the battery to the frame. I cleaned that real well and she fired right up and ran like a champ!!!. I guess the lesson is don't ignor the obvious stuff that stare's you right in the face.Here is the newly painted sheet metal, and new decal set will be here Tuesday from re-do-my horse.com. Can't wait!!

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