Electrical problems

[cdixon311]

I don't know much about the electric system, except that I f-cked it up. I'm in the process of getting a used motor to run. My idle has been all over the place and I'm blowing my 70amp battery fuse. I guess I should also mention that I blew the fuse on a test run and replaced the fuse with a piece of speaker wire to make it home. (go mcguever) My engine was also making a loud noise that I thought sounded like my timing was off and the valves were hitting, but I knew that it wasn't. and after talking with a friend, I decided to remove the transmission and redo my clutch, this time using a clutch alignment tool instead of a socket.

Before I arrived at that decision I had the motor idling and loosened my clutch cable alittle bit. (the car is in nuetral) When I did this the rpms dropped dramitically and the car sounded good for a second, but then the rpms dropped the rest of the way down until my car stalled on me. While the rpms were falling the piece of wire in place of my battery fuse began to heat up, and melted through. Since then when I turn the key to the on position abosolutely nothing happens, but my interior overhead light, horn, headlights and cigarette lighter work. The radio doesn't come on either.

Any ideas what I broke this time before I haul it off to a mechanic?

[Mac]

There is a big white wire that goes to the alternator. Check that, make sure that it is not touching any bare metal anywhere. Look where it hooks to the alternator, make sure it is tight and only touching the stud and not the body of the alternator. Then follow it back and look for any bare wire that is touching metal.

[cdixon311]

I have checked this wire the other day and it didn't look like its touching anything. Back at the very begining when I dropped the motor in this wire was touching and sparking all over the place, I rewrapped it in electrical tape and put it back on. I tested the altenator before the car went dead and it tested fine, or so Doyles said.

[Mac]

Looking quick at the wire daigram for an 88, I don't see much else that would blow that fuse. That fuse is right off the battery and feeds other fuses in the relay/fuse box. It looks like all that comes off that fuse (besides the other fuse feeds) is the alternator wire. I'm not sure if an 89 is wired any different.

I would go back and check it again. Make sure it is hooked up to the alternator properly, and that you taped up all the bare wire all the way back to the fuse.

Another thing to check would be the feed to the other fuses off the 70 amp. Maybe something got fried when it first arced, and is now shorting out.

[cdixon311]

I'll go back and check all of that one last time, I'm thinking about getting a new wiring harness I found one for under ten bucks. If your talking about looking inside of my underhood fuse box, I took a look in there and ventured down to the second level under the fuses, everything looked fine but I was scared that I would get something out of place so I put it back together.

[cdixon311]

Aside from that what do you think I might have fried that prevents the car from coming on?

[Mac]

Check fuse #25 (40 amp) in the under the hood relay/fuse box. It is fed by the 70 amp and feeds the ignition switch and starter solenoid.

[cdixon311]

All of my large funny looking fuses are fine. I looked over the rest of them and didn't see any broken fuses. But i don't think its the starter/ignition. The thing is when I turn the car to the "on" position nothing comes on. no dash lights, no fuel pump, etc.

[Chadroper]

Do you know if you have a short somewhere? Have you tried metering the circuits? If you have a short in one of them if you meter across the short you will measure almost 0 vDC and very high amperes. If you have an open you will measure the supply voltage 12 vDC and 0 amperes.

[cdixon311]

Like I mentioned before I don't know much about electrical, I understand what your saying chadroper, but could you explain how I would check this. Thanks.

[Mac]

Another fuse you can check would be fuse #2 in the under the dash fuse box.

[Mac]

Just one more thing. If the 70 amp fuse is no good, you won't get nothing with the key on. As I said earlier, the 70 amp fuse feeds the fuse that feeds the ignition switch.

[Blkblurr]

If you lost a 70 amp fuse, any other fuse in the short path will be blown because the 70 amp fuse is the largest so the others would have blown first. It's doubtful that it's on any other circuit other than the 70 amp main branch unless you replaced other fuses with wire. (can cause a fire) I suspect you have a cut wire that's touching the body of your car. Maybe a short to ground in your fuse box. Do you have any wire melt damage? If so where is it. This will help determine where the short is.