• Hello there guest and Welcome to The #1 Classic Mustang forum!
    To gain full access you must Register. Registration is free and it takes only a few moments to complete.
    Already a member? Login here then!

ok Duane, this ones for you...

R

RustyRed

Active Member
Duane, this one is specially for you as payback since I messed with you about forgetting to tie down your battery a while back.

Changed out the water pump on the Trans Am the last couple of days in addition to resealing the rear end. I did something really stupid this morning and could just kick myself in the butt about it.

Started the car and it was running ok. Then I noticed the volts gauge was reading zero.

Pulled the car back in and sure enough when I was putting the front of the motor back together totally forgot to plug back in the alternator. Got distracted by kiddos and then forgot about it when I went back to working on the car....oops!

I had let it idle for several minutes so my guess is the battery is dead but that's not the big problem.

The big problem is like a moron instead of unhooking the negative battery cable first thing I started checking what I might have forgotten that would have caused the zero volts reading. I accidently bumped one of the loose alternator wires and zap....then I heard a frying sound (for lack of a better description) travel down the harness back towards the firewall with a cloud of smoke, etc. I was just glad I didn't catch something on fire but it caused a serious short to say the least.

The wires under there looked pretty old and brittle anyway but my guess is I've fried them and need to replace them for sure now...the engine harness I can find for about $150 and it probably really needed replacing anyway but I am taking a wild guess I don't have a choice now. I know there was smoke coming from the wire that attaches to the alternator for about the length of say an Olds 403...

The car is totally dead and could be just a really dead battery but when you turn the key...nothing, not even the radio and that's after an hour on the charger at the 10 amp setting.

Guess it's only money but I figure I'll be out the cost of the wire harness and probably a new battery before it's all said and done.
 
Wow, that's amazing. I was just doing something on my alternator a week or so ago and still had the battery connected. The nutdriver I was using contacted the head, got a few sparks, but not catastrophic failure. I'm thinking I got lucky if what happened to you is normal.

All that from a momentary short?
 
First time I ever changed an alternator I was about 16 years old and in a hurry. I forgot to unhook the battery, grounded out my wrench on something and got what you got...a couple of sparks and a good zap but that was it.

These wires are looking pretty worn / old / brittle anyway and doesn't look like a hard replacement. Looks like the harness plugs in at the firewall then runs to a few things like the alternator, temp sending unit, oil pressure unit, etc.
 
Just thought of this, but after I did that thing with the alternator my stereo didn't work. Turns out it managed to blow a fuze but did no damage otherwise.

If you are getting no power at all to the car, check the fuzes. With the battery charger hooked up, you should have enough juice to run some accessories.
 
That sucks man. I, however, would NEVER relish in someone else's misfortune....but my doppleganger might. Check the fuses. You may get lucky. Good luck.
 
Hauled the battery over to Autozone and it had a bad cell.

Installed new battery and still zero when I turn the key.

I've never heard wires fry like that so I am going to order the harness since it looked old anyway. I don't see any obviously burned out fuses in the box but may have a closer look.

My hunch is that normally you would get a little zap at the point of contact and that's it unless you have really old wires....

I'll get it fixed but been doing a lot of cussing about it today....$94 for a battery so far and the harness is going to cost me ~ $150....lesson learned = priceless :thu
 
Granted I'm thinking about this in terms of a mustang harness, but I'm wondering how a fried engine harness would affect battery power to other circuits. You should still have some power on the accessory.
 
No power to acc. if the main power to the interior runs thru that same harness. Only guessing without a wiring schematic... Could fry the new harness also if something else got damaged.
 
I was doing some more looking at it this afternoon. It appears to me that part of that harness has been cut out at some point and different wire spliced in. Lord only knows what kind of wire, if it was correct gauge automotive wire, etc.

It seemed to only fry the section in question. I was standing right there....it was like a fuse or line of black powder burning.
 
"blue65coupe" said:
May have been a blessing in disguise.
Click to expand...

Yep, I was thinking the same thing. Especially since I haven't gotten around to dealing with the leaky carb that needs a rebuild.

That wire appears to go straight into the fuse box via a plug in the firewall so I am thinking at most it might have blow a few fuses. None of them looked blown though when I had a quick look see. Honestly, I think we've all gotten a good zap from grounding out alternator wires on accident before. Usually not a big deal other than your hair sticking straight out for a time. At first for a split second seemed like no big deal but then it seemed to jump past what would appear to be factory wire to the spliced in wire and the spliced in wire burned up in what I can only describe is like a fuse on a bomb burning.
 
"sigtauenus" said:
Do fusable link wires burn out like that by design?
Click to expand...

No tengo ni idea... sounds like a question for Midlife...but this is kind of how the wire burned... :bomb
 
"RustyRed" said:
No tengo ni idea... sounds like a question for Midlife...but this is kind of how the wire burned... :bomb
Click to expand...
Negative...they are a short piece of wire that acts like a fuse. The short section will burn out, then stop the current flow.
 
You must log in or register to reply here.
Back
Top