MEP 802A What happened here?

[Barney File]

Bought 2 802s recently. Once I got them home, I started working on the lower hr one (which I will gift to my daughter). Charged the batteries, checked the fluids and gave it a quick look over. Found a couple bad connections which I repaired. Cranked it to see if it would produce power. Started and ran well. Figured I would put it under a quick load test which went well (4 heaters equaling 5850w. 3 1500 and 1 1350 ).

So started rodent proofing and noticed a wire's insulation was roasted. Checking the wiring diagram it is the #12 ground at the top Starter mounting bolt which attaches to the ground lug at the output terminals. No connections in between. Wire is 100E12. While tracing the physical wire I removed the front cover. Noticed the wire on TB4 #9 to PPgnd was burnt in two. Looks like an old fault, not new. Any idea what could have been the cause of this? Anything I should look out for?

Also, any reason the designers routed the 100E12 wire all the way to the starter (about 4 foot total) when they could have easily grounded to the motor on the oil pressure side of the engine other than to save the price of a bolt? Any reason I couldn't ground it there?

 

[NDT]

Possibly someone used jumper cables and hooked the negative cable to the chassis rather than the battery, which caused high amps to flow through the light gauge wires.

 

[Ray70]

Or possibly hooked up jumper cables in reverse polarity with + on the chassis and - on the + battery post??
Look like some kind of dead short/reverse polarity situation happened at some point.

 

[2Pbfeet]

Or hook up the wires to the terminal board incorrectly.

I had that wire burned up in a generator that I bought. Hot tip: it is not listed in the TM. @Guyfang put me on to it here;
https://www.steelsoldiers.com/threads/new-to-me-mep-803a-with-a-charred-ground.215947/post-2526448 10ga TGGT wire.

New to me MEP-803A with a charred ground

Upfront, I just want to say how invaluable this forum is. I have been reading for a few years, and it gave me the confidence that I might be able to get an MEP-803A up and running. Not there yet. But I bought one. Backstory: I just picked up an '06 MEP-803A, with 22 hours on it. Given the age...

www.steelsoldiers.com

All the best,

2Pbfeet

 

[Barney File]

Or hook up the wires to the terminal board incorrectly.

I had that wire burned up in a generator that I bought. Hot tip: it is not listed in the TM. @Guyfang put me on to it here;
https://www.steelsoldiers.com/threads/new-to-me-mep-803a-with-a-charred-ground.215947/post-2526448 10ga TGGT wire.

New to me MEP-803A with a charred ground

Upfront, I just want to say how invaluable this forum is. I have been reading for a few years, and it gave me the confidence that I might be able to get an MEP-803A up and running. Not there yet. But I bought one. Backstory: I just picked up an '06 MEP-803A, with 22 hours on it. Given the age...

www.steelsoldiers.com

All the best,

2Pbfeet

Thanks for the reply. Very informative post.

 

[Barney File]

Ray and NDT: Possible but wouldn't think so as this was a gov surplus sale unless the slave was wired incorrectly at the reset?

 

[Ray70]

It could depend on where you bought it. Some of the auctions attempt to start them, some don't, some use a slave cable, some don't.
I got one once with the throttle cable jacket melted somehow and my best guess was that somehow someone tried to jump it and had a mishap with the cables???

 

[Light in the Dark]

It could depend on where you bought it. Some of the auctions attempt to start them, some don't, some use a slave cable, some don't.
I got one once with the throttle cable jacket melted somehow and my best guess was that somehow someone tried to jump it and had a mishap with the cables???

Are you saying its a bad idea to clamp both + and - jumper ends to the chassis? Won't the electricity find its way to the starter eventually?

 

[Ray70]

Perhaps it was really cold out and someone figured the spiral wound throttle cable sleeve would make a nice resistive heating element to pre-heat the engine compartment??

 

[Guyfang]

You guys are bad!