520 onan will not start

[budman2 57]

Does anyone on this forum know what would not let my 1992 520H onan not turn over? I have eliminated every part that I can think of! Any help would be appreciated, thanks budman2

[troutbum70 858]

Maybe a safety switch, take power from battery straight to starter see if she will kick over that way.

[ZXT 2,401]

I have to ask, what is your definition of "wont turn over"? As in the engine doesn't spin over or it just won't start? I see people all of the time using improper terms, and it certainly doesn't help the diagnosing process.

 

Have you verified that you battery is good? I know Richard will be along soon to suggest load testing.

 

If you own a volt meter, check the battery voltage at rest, and see what it is when you have the key held in the start position. If it doesn't drop hardly at all, it's likely that the battery isn't your issue. If it drops to nothing, then it needs a battery.

 

Have you checked the fuses or any of the electrical connectors? The connectors, especially at the ignition switch and those connecting to the main harness can corrode and will either burn up the connector or simply lose connection altogether. Do you have power at anything else, such as your lights?

 

 

Edited October 17, 2019 by ZXT

[PeacemakerJack 10,743]

Agree with above...

 

—if you know the battery is verifiably good, because that is a HUGE problem with these new “cheap” foreign made batteries 

—I recommend bypassing everything and try a direct to starter jump first. If it jumps to life, then you have to work your way out

—beware of the simplest thing. My sons 418-C has a “goofy” safety switch on the PTO. Sometimes you turn the key and nothing. Wiggle the PTO lever a little and it starts right up. 

—if as @ZXT just mentioned, you turn the key and it turns over but won’t start, there is a little different series of diagnostics 

[budman2 57]

I think I will start with a new battery! tried everything else that has been mentioned, thanks for the input ! budman2

[Ed Kennell 42,063]

Have you tried the direct jump from the + battery post to the starter post as suggested above.     It is best to locate the problem.   Adding new parts that may not solve a simple connection problem can be expensive and frustrating.

[richmondred01 2,307]

Is one of the relays making it a clicking sound?

[budman2 57]

One of the relays is making a clicking sound!

[richmondred01 2,307]

1 minute ago, budman2 said:

One of the relays is making a clicking sound!

Yes,

when you turn the key to start do you hear a faint clicking sound from under the battery tray area?

[budman2 57]

Yeh what does that meen? bad relay?

[richmondred01 2,307]

Not necessarily. Remove the relay, and tap it. The contact inside may be stuck.

[tom2p 2,394]

might also be a bad battery 

 

 

[budman2 57]

Just put a new heavy duty battery in it, doing the same thing! nothing. Starter checks out fine on bench, can't figure it out! budman2

[richmondred01 2,307]

Did you pull the relays?

 

[lynnmor 7,829]

On page 7-99 of the demystification guide you will see the chain of connections necessary for the starter to run.  First jump from the small light blue wire on the solenoid to the large battery cable to see if the starter runs, then start chasing down bad switches and relays.

[WHX?? 51,791]

I'm guessing you checked the 9 pin? Fuse sockets? Grounds?

[953 nut 60,108]

[ZXT 2,401]

3 hours ago, budman2 said:

Just put a new heavy duty battery in it, doing the same thing! nothing. Starter checks out fine on bench, can't figure it out! budman2

Did you listen to a thing anyone has posted? Not to be rude, but it seems that you asked for suggestions, got them, and instead of trying to diagnose, you ignored the suggestions and threw parts at it.

 

It's likely very simple. Jump across the starter solenoid. It's been suggested 4 times already. 

[Darb1964 1,119]

Not rude, ZXT. I thought it was just me! JUMP the dang starter!

[budman2 57]

OK boys here is what I found, the relays and relay sockets are burnt up! Thanks budman2, not to be rude back but I had already checked those items as listed!

[ZXT 2,401]

1 hour ago, budman2 said:

OK boys here is what I found, the relays and relay sockets are burnt up! Thanks budman2, not to be rude back but I had already checked those items as listed!

But you never posted back your findings. If you'd said "The battery tested good and the engine cranked over when I jumped the solenoid", it would've given us a better idea of what your issue was. 

 

And I apologize for assuming you hadn't tested any of it. I just figured if you had, you wouldn't have needlessly replaced your battery. 

[953 nut 60,108]

8 hours ago, budman2 said:

I found, the relays and relay sockets are burnt up!

Any good auto parts store can sell you a relay socket. While you are there pick up some dielectric grease and use it up on every electrical connection you have.

[richmondred01 2,307]

I’m pretty sure I have the relays and sockets on a wiring harness.

PM me if you want me to dig and find the harness. 

[budman2 57]

The sockets are the hard parts to find for me! I guess they are part of the wiring harness. If you have one you can part with please let me know, I can't seem to find those! Thanks in advance guys for the help, budman2

[richmondred01 2,307]

I only have the complete harness.

 

Edited October 20, 2019 by richmondred01