I imagine there are a lot of folks that say the same thing about Porsche repair shops until they have to bring their car in on a flat bed with extra damage from their DIY repairs.

If you look at the very first picture in this thread, you can see that the connection that is now a problem was already corroded. You need a new box, and you need to figure out if the wires running out of the box are sufficient for your load, although they probably are.

I would use a pro, and I would get it inspected and approved. There are liability reasons for the above, and even though I know a lot about electricity, that is the reason why I would want someone else to do this job and have it inspected.
Also, If I were renting a place, I would consider this to be at least partly the landlords responsibility as regards repairs, unless I were intending to upgrade the system.

That box is literally toast. I had a similar problem in my house, and I replaced the box and upgraded to a 200 amp system, at which time I upgraded the system in my shop to 100 amps. I never looked back.

This could all have been done some time ago, and done right. I'm pretty sure that at some time in the recent past, that screw was red hot, as in RED hot. Electricians are usually licensed and insured, as are inspectors. It is in their best interest to use their knowledge and experience to do a good job for you. They have seen all this 100 times.

At some point I would have to ask myself, ''Well, since I didn't foresee THIS, what else don't I know ?''. Aside from having good connections, code compliance requirements have changed over the years. You want to be in compliance, inspected, and have a trail of liability heading away from you, unless you have the kind of insurance that will cover you in any foreseen or unforeseen instances heading into the future.

New work needs to be inspected, and you need a new box. That one is toast. Done, dead, deceased.

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''This Parrot wouldn't move if you put 4000 volts through it. It's bleeding demised...''

Be sure your home (fire ) insurance is paid up.

Yes, because Sooner or later....

A couple of notes...

The line wires look to be the same size as the load wires, so the pole fuses are likely 100 Amp, the code applies to the service provider too.

You might have an unbalanced load, I would guess the center phase sees close to 100 Amps regularly. You could address that with some rewiring, but I don't think it's worth the effort. You know how to fix it.

You have proper sized conductors and a working breaker (I think). The risk of a fire is minimal.

You could do a few tests with a clamp on ammeter, you may have outgrown your 100 Amp.

So not barefoot on a wet copper plate that's sitting on bare ground while using the plug in blade for an interchangeable screwdriver?

Don't forget the battery clamps on my nipples. ACDC, gotta love it.

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Thank you! I disconnected the center blade today. While I look for an electrician, it would be easy to make a 4 gauge wire connector with terminals that would bolt to the bus bar and plug in to the breaker. But won't have time for that this week so just going to leave it as is and start the search. Many thanks for your and dad's continued help.

It's almost been a month. Did you get an electrician to take a look at this breaker/box?

No, I ended up making the 4 gauge jumper that has worked perfectly, and will continue to I'm sure. Was checking every day, now once a week... it hasn't gotten hot or corroded or anything. But I am going to TIG together a new breaker to bus bar attachment and have it either cadmium or silver plated. The aluminum one I took off is absolute garbage. I'll probably make 2 other breaker to bus bar attachments this summer to replace the other two aluminum ones though they are fine, no corrosion, no sign of getting hot.

In this end, this was a very simple problem: the aluminum breaker to bus bar attachment was junk. Making a new one with solid clean connections has solved the problem. Definitely don't need a new breaker box.

coming up on a year later and my repair has worked perfectly.

It was failing under the oppression of Obama.

Now that Trump is making America great again your breaker can thrive.

Remember that when it's time to vote!

:D

Lol! :D

There are lots of sprays you can use to prevent corrosion.

And some you can spray on live wires.

Maybe it is all the equipment you have installed in the place. You still don't know what the problem was, so you can't possibly know if you have fixed the issue.

In reading through this thread, I have come to the conclusion you don't have as much sense as I had thought.

You do realize that if there is ever a problem or someone gets hurt, this thread will hang your ass, right?

No corrosion in a year. Clearly the original poor quality materials are what failed, and continued to fail. My high quality repair will outlast the rest of the box.

You have the approval of at least one electrical engineer.

Your solution is better than another cheap aluminum box from Mexico.

Thank you. If I had time, I would rebuild the whole thing. But it's been working for a year so I'm going to leave it alone for now.