Fuse #1

[Helirich]

So after completing a lot of work on the car, it still doesn't run good after warm up. (It runs good when cold) I've been checking lots of stuff and just happend to feel all around the fuse box. The #1 fuse is hot and the wires going to it. The #2 fuse has been moved to a stand alone fuse. Do I need to do that to #1?

Not saying this is my problem, but it is not good.

[82DMC12]

So after completing a lot of work on the car, it still doesn't run good after warm up. (It runs good when cold) I've been checking lots of stuff and just happend to feel all around the fuse box. The #1 fuse is hot and the wires going to it. The #2 fuse has been moved to a stand alone fuse. Do I need to do that to #1?

Not saying this is my problem, but it is not good.

Not many amps running through that fuse. Likely the fuse is just dirty or has a bad connection in the fuse box. Which RPM relay are you running? You still have the original fuse box?

https://support.delorean.com/kb/a52/fuse-box-and-melted-fuses.aspx

[Helirich]

Not many amps running through that fuse. Likely the fuse is just dirty or has a bad connection in the fuse box. Which RPM relay are you running? You still have the original fuse box?

https://support.delorean.com/kb/a52/fuse-box-and-melted-fuses.aspx

I removed the fuse and cleaned the spades, but it still got warm in a short drive.

I don't know which rpm relay I have. What should I look for?

I have the original fuse box, or what's left of it. In your link, it has a pic of a melted box. It says this is an extreme example. Well that box looks fantastic compared to mine. Lol. I did order a new box a few weeks ago. It's waiting patiently for me to install it.

[David T]

It is not unusual for fuses to be warm to the touch. Too hot is no good. #7 is notorious for melting the fuseblock. My guess is that when the fuel pump goes bad, before it quits, it draws too much amperage. Not enough to blow the fuse but enough to melt the fuseblock until, finally, either the fuse blows, the connectors can't make good enough contact, or the pump fails completely. Common to see an in-line fuse holder used to power the circuit after melting #7 out. A cheap, quick and easy fix but not a professional way to do it. You also usually see the heater circuit inside the CPR burnt up too. It does take a lot of time to fix it right by replacing the plastic fuseblock and putting new connectors in the #7 spot but if you want it fixed right, that's what it takes. Leave the cover off the fuseblock and inspect it at least annually. If you have the jumpers for the Fan Fail Relay, they should also be inspected at least once a year too. Make sure the connectors still have "spring" to them or they will not hold the fuse tight enough to make a good connection. That makes things hot and the hotter they get the less "spring" they have and then things start melting. Also a good idea to remove each fuse and verify it is the correct size for it's position. All too often a fuse blows and a PO will stick whatever is handy back in to get things going again. I keep a small bag of fuses in that area just in case so I have the correct size if necessary. I never had to use any but sometimes I need them for someone else's car.

[WHO1DMC]

I removed the fuse and cleaned the spades, but it still got warm in a short drive.

I don't know which rpm relay I have. What should I look for?

I have the original fuse box, or what's left of it. In your link, it has a pic of a melted box. It says this is an extreme example. Well that box looks fantastic compared to mine. Lol. I did order a new box a few weeks ago. It's waiting patiently for me to install it.

My own experience with this problem is that the pins in the fuse box got so corroded that it went into the wires. So no matter how good your fuses are it my not make a difference. When I replaced my fuse box I saw evidence of this a specially with the melted areas. Keep in mind that DC current flows better on the outside of the wires. So if there is a lot of corrosion there is more resistance therefore more heat.


Take it one wire at a time.

Dave B.

[82DMC12]

I removed the fuse and cleaned the spades, but it still got warm in a short drive.

I don't know which rpm relay I have. What should I look for?

I have the original fuse box, or what's left of it. In your link, it has a pic of a melted box. It says this is an extreme example. Well that box looks fantastic compared to mine. Lol. I did order a new box a few weeks ago. It's waiting patiently for me to install it.

Just wondering if you have an OEM RPM relay or Dave M's relay like I have. It goes through Fuse 1.

My fuse box was a melty mess when I got my car 20 years ago. It had five or six jumpers in it. About 10 years ago I replaced my fuse box and crimped all new connections into it using the right tool (which of course I never used again...). But totally worth it. Still looking good today though I think, after reading this thread, it would be wise to check my fuses for oxidation.

That was a long day of soldering and crimping. Might still have the burns on my fingertips to prove it.

[David T]

Typically, when you see corrosion in that area, either the car was left open to the weather or animals (rodents) got in there and urinated. Either is bad and all the corrosion must be removed. If it is really bad you have to cut it out and replace the wires, connectors and fuses. I have seen it so bad it gets inside the wires and can travel inches into the wire from the end inside the insulation. If the car got flooded the whole electrical system could have to be replaced, especially if it was salt water. BTW, AC flows on the outside of wires and the higher the frequency the more the current flows on the outside. DC flows evenly over the entire cross section of a wire. At the levels of current in most automotive applications it is not a factor.