I was changing the belts on my '72, when I realized I needed to disconnect the alt. wires prior to dropping the alt. down for belt change. Yup, forgot to diconnect the neg. battery wire and pow, gounded it out. Big flash. Now the car is dead. No lights, won't turn over, nothing. Background on the car: BB 4sp HEI. No starter switch (you don't have to engage switch at the floor to start).


Chris

Any power to the horn relay? Measure the threaded stud on it to ground. Should have 12 volts. Horn relay is next to the brake booster.

if you don't have power at horn relay ..... you've blown the fuseable link in the main power wire .... I'm not sure on 72 if its up at horn relay or down on starter :confused: my books at work

Thanks, the book I have says that if everything is dead, given the fact I grounded it out, it's probably the fuseable link.


Chris

horn relay is on firewall next to power booster

Opps..... graemlins/clonk.gif that should have said power brake booster .... or just master cylinder if you don't have power brakes.

I found the box. It looks like a relay box to me. It has a post in front with three wires on it. There are two seperate wires terminated underneath. My meter is at work so I can't test it. Is this also the fuseable link. If not what does it look like.

Thanks,

Chris

I *think* on a 72 the fusible link is the wire with an eyelet terminal on the starter post along with the positive battery cable

(about the first 4 inches or so of the wire)

yep.... thats the one those large wires are the power wire from starter & power going to fuse box depending on options on car they might go to AC or power top or seats allso..anyway .bottem plug in wires are to horn ...you need to check power on this relay if you've got no power ...read the post before this one... smile.gif

Thanks to everyone for the help. Also, is there an upgrade for a fuseable link. Some type of breaker or module that I can wire in.


Chris

upgrade fuseable link :confused: ..... I wouldn't its in a very tight spot right next to starter & block sandwiched between exh system... not much room down there ...also its in a little tube to protect it from the heat ..so mounting any kind of circut breaker would be HARD to do.. sure you could mount up top on firewall but the closer to the power sorce the fusable link is the better ..when you replace it do it right .. you don't want a bad connection here..no quick crimp fitting.. butt fitting solder & shrink fit graemlins/thumbsup.gif

Dean thinks right. The fusible link is down under. Still haven't heard if there is 12 volts on the horn relay stud.

Hi to all. Got the meter and tested the relay. Got no voltage at the two horn wires. I got no voltage from the front stud of the relay to neg. terminal on battery. However, I did get voltage from the pos. terminal to the same stud, and I did get voltage from the terminal on the alternator and the positive terminal of the battery.

There's a wire on the horn relay stud that runs down to the solenoid/starter large stud. If the horn relay stud has no voltage to ground, check out the fusible link in this line. It's the soft thing right above the starter that's in this wire.

Thanks for the help. I'm fairly sure that the fuseable link will be it. No matter what I do, it seems I learn more from mistakes than anything else. I'll let you know when I'm back on the road.

Chris