I just got a 76 vette and everything power goes down real slow (windows, lights) and the heat and air, radio don't work and the battery gets completely drained in like 10 min, even when the car is moving. The guy thinks its the alternator but i think it is alot more than that. anyone ever have trouble with something like this? I appreciate any help i can get

A good battery won't drain that fast with a dead alternator. BUT if the alternator has shorted diodes it can actually put a short into the system, draining every thing very quickly. 10 minutes still sounds short unless the battery is weak. If the battery stays up with the key off, look for a short after the ignition switch. Any constant hot lead can be a partial short that could occour only with the key on. Start disconnection things one at a time and see when the drain goes away. Use a volt meter to watch for a voltage change. This likely something on a main power circuit or circuit breaker. That much of a short would likely blow a fuse. I would start with disconnecting the battery lead on the alternator, and go from there.
Keep me posted on what you are finding, and I can help track it down.

The first place to look would be the alternator. Easily checked at your neighborhood auto dealer. (autozone, advance, napa, pep boys, etc). If you are charging up the battery and after 10 min it is going dead, then it is definitely not charging. Could be a fuse blow, wire corroded, etc. Could be a short, drawing all the voltage. The place to start is to ensure that the alternator/voltage regulator is working. I just replaced a alternator that come apart on the inside, and even then I was able to drive over 15 min till I got home, with he lights on. You can get the battery checked out also at the same time, to ensure that it does not have a shorted cell. Once these two components are checked, then I would start disconnecting as recommended next. You have to have a good charging system between the alternator, and the battery before anything else is able to work. Keep us informed what you find, or any other questions.
Bill.

Hello all,

I agree with the alternator theory. However, don't just install an alternator and try that. Take the battery along to the parts store and have tham load test it.

Many times the battery will be the root cause of the problem because it gets an internal short causing an over current in the alternator thus blowing the diodes or regulator.

The headlights go up and down via a vacuum system. Check all of your vacuum circuits to ensure you have a sealed system. If the system has leaks everything will be sluggish and the hp will be low.

There are wiring and vacuum diagrams available from http://www.vettespecialties.comif you need them or call 303-888-6577.

Congratulations on your new purchase.

Alex

Thanks for the responses. The guy i bought it from just put a new hose for the headlights so i do not think it is that. Overnight i took the key out and the battery draind slightly, not nearly as much as it did when it was running. Also, there are three exterior key holes for alarm systems which are disconected. The tach, oil pressure, clock, all gauges are infunctionable. Also, the heat and a/c is disconected. I am pretty sure now it is a short somewhere. Where should i start?
p.s. i cannot figure out how to put the hidaway headlights down, help? I am also looking for bumpers f/b for my car. Is the bumper one piece or is it two corners? Does anyone have a 76 that they want to part out? Thanks for your imput

76 ''ray said: p.s. i cannot figure out how to put the hideaway headlights down, help?

I can help you with the headlights - having just gone through that experience! In the diagram below, there is a hinge controlled by the actuators. The hinge has a pin going through it (circled in RED). If you reach up under the front bumper, you'll see this. Grab the hinge at the pin and pull down. You have to pull harder than you may think to "release" the hinge. When you do, you'll see the headlamps close. Don't push them down or you could damage the actuators.

I took all the fuses out over night and there was still a slight drain on the battery. I then got the alternator checked and is was good putting out 14 volts. I swiched the heads from a snipped wire from the original alarm, and suddenly i got a normal charge instead of a discharge. The guy i bought it from has done some major hacking wires so all i could think of was to check the battery in the morning and see if it still drains, which i think it won't, and also take apart the whole wiring harness and check to see if everything is hooked up right. I got unplugged wires all over the place and do not know where they go. The engine starts right up and at least the alternator is charging the battery and all my gauges work. The radio though new does not work, neither does the tach, but i think they are seprate wirings from the fuse box right? I do not know much about electrical but am glad i am getting some headway here. thanks for the help

My tach didn't work on my 75 when I first got her. There is a circuit just for the tach, located behind the tach itself. In my case, I ordered the new circuit, which fixed my tach, but with all the wiring problems you have, I might not jump right on that. Chances are, the circuit is bad though. As far as the radio, you can check to ensure that you have a good ground and a good positive. You will have have normally two positive leads, one will be hot all the time, one only when the key is in the ACC postition and also when the key is in the run position. Again, the one that is always HOT should be 'yellow'. The other positive wire should be 'red', and ground would be 'black'. I recommend purchasing a wiring diagram, to help you get your wires all hooked back up. They aren't much, and one will pay for itself over and over in the long run.

What a nightmare! Brings back all those memories. I bought my '74 in June 2002.
The wiring was all mixed up. Should a wire start out as blue, be sure it will become brown - pink - red - yellow to the end. This is a major hassle.
Also on the altenator we found that it does not charge the battery once the earth is connected to the altenator. (The altenator was tested and found to be correct and 100% working).
Should your wiring be anything I experienced, I suggest you get a good wiring diagram for your year model. Secondly, try to get the experience of a reputable electro-mech.

All of the best.

Elmien

I would get a good exploded wiring daigram from one of the catalogs or Lectric Limited. Just start tracing wires and make sure you have continuity. With all the things that don't work, there is bound to be broken wires somewhere. Wiring harness aren't cheap, but many Vettes have burned due to faulty wiring. If you replaced the wiring, you should have another 27 years until you have to worry about it again.