New to me MEP-803A with a charred ground

[2Pbfeet]

Here are the wires that I have no idea where they go.

To the extent that you can follow the chewed end and get a wire number, that will tell you which wire it is, and then you can look at the schematic to find the two ends, and double check with a DVM that the frayed bit goes to where you think does.

Similarly on the contactor, you know which terminal the chewed wires are attached to, and you know which wire they aren't (the 10ga power wire), and again, if you check the schematic for, say, B1 on the contactor (K1) you can see that there is a second wire attached that goes to terminal 20 on switch S6. My schematic is a bit mangled, so I can't tell if it is 002E or 002F. I suspect 002E. The schematic gives you a couple of different ways of looking at things; one by the overall schematic, but also the wire numbers that connect particular pieces with notation on where they are to be connected. So you get several views of the same wire or connection. I am a complete NOOB, so I may have misunderstood your photos and / or the schematic.

Basically, until you unscrew a wire, you have several different ways to figure out what it is and where it goes.

Does that help?

All the best,

2Pbfeet

 

[Guyfang]

Here are the wires that I have no idea where they go.

Using the wire diagrams, you should be able to easy fix this damage. Wont say it will be fast, but its an easy fix. Here I will say, check every wire in your hand, 3-4 times. Then maybe ONE more time. You need to be 1000% right, on every one, or you might be trying to find a whole wire harness. Don't assume, check EVERYTHING, and KNOW. In your shoes, I would have someone with me to help. Two heads are better then one. Use a good multimeter and have a foolproof way to mark a wire so it will not come unmarked.

 

[Guyfang]

This will also help. Its 99.5% right.

 

[2Pbfeet]

Using the wire diagrams, you should be able to easy fix this damage. Wont say it will be fast, but its an easy fix. Here I will say, check every wire in your hand, 3-4 times. Then maybe ONE more time. You need to be 1000% right, on every one, or you might be trying to find a whole wire harness. Don't assume, check EVERYTHING, and KNOW. In your shoes, I would have someone with me to help. Two heads are better then one. Use a good multimeter and have a foolproof way to mark a wire so it will not come unmarked.

Sounds like advice born of long experience.

Do you have a recommended foolproof way to label wires, or at least a favorite one?

All the best,

2Pbfeet

 

[odge]

Thank you, all. I have my work cut out for me. Taking a four day weekend this next weekend so I should have some time to start doing this.

Do you recommend replacing these wires end to end rather than a splice. That is my plan anyway, just wondering what your advice is? I did not think to hand check every wire but will do so now that you recommend it.

I have a multi meter and can check continuity but checking ohms and resistance is more than my knowledge base at this time. I know just enough to get me into trouble.

I don't have any way to label wires at this time but it I have been thinking about how to do it.

Thanks,

O

 

[odge]

I am also planning on replacing the one terminal strip that has rodent waste on it and some of the terminal end.

 

[2Pbfeet]

Dymo makes heat shrink wire labels; I just don't know how stable they are longer term, especially with regards to heat.

 

[odge]

Thanks 2Pb...that is a dang good idea!!!

 

[2Pbfeet]

Thanks 2Pb...that is a dang good idea!!!

Just bear in mind, I have never used them in a location that gets hot and stays hot. According to the Dymo specification sheet, they are good to 257F/125C.

https://download.dymo.com/dymo/technical-data-sheets/heat-shrink-tube-technical-data-sheet.pdf

(Not pushing this particular brand; it just happens to be the one that I have used.)

 

[Guyfang]

Its not that hot in the AC section. So go ahead and use the DYMO. We had some wire ties that had a tag on it. You could write the wire # on the tag. What ever you think will work for you. Some of the wires I would compleatly replace. Like the one that goes to the PP Ground. Its short, easy to do. If you decide to change whole wires, put some wire ties on the harness, loose, not tight. Then, if you can pull out whole wires, reinsert the new one. When done, tighten up the new wire ties, and clip out the old ones. Keeps things cleaner looking.

 

[Farmitall]

 

[Guyfang]

Exactly. Maybe a tad smaller, but that's about we used.

In later years, when some of the sets we fixed were in the can point, I would take compleat wire harnesses, and strip individual wires out. So the wires looked like they had never been damaged. But you can do that when you have 12 guys in the section.

 

[Farmitall]

Exactly. Maybe a tad smaller, but that's about we used.

In later years, when some of the sets we fixed were in the can point, I would take compleat wire harnesses, and strip individual wires out. So the wires looked like they had never been damaged. But you can do that when you have 12 guys in the section.

I think those are the small ones and the picture is just a close up. I use to use those frequently doing mobile radio installations and building power supplies.

 

[odge]

Will your run of the mill heat shrink connectors be sufficient in the AC section.

 

[odge]

Using the wire diagrams, you should be able to easy fix this damage. Wont say it will be fast, but its an easy fix. Here I will say, check every wire in your hand, 3-4 times. Then maybe ONE more time. You need to be 1000% right, on every one, or you might be trying to find a whole wire harness. Don't assume, check EVERYTHING, and KNOW. In your shoes, I would have someone with me to help. Two heads are better then one. Use a good multimeter and have a foolproof way to mark a wire so it will not come unmarked.

Thanks for the advice. I was out checking wires (before is started to rain) and found 4 more 20 AWG wires that were chewed up.

 

[odge]

Hey everyone, I was able to successfully start the generator up and put a small load on it through the front 10 amp courtesy outlet.
Thanks for all your advice on the project.