Electrical stuff

[dubie]

I dug the 72 out today and took it over to the shop so I can work on it. I brought it out of winter storage for a couple weeks for a Christmas parade. I knew when I put it away that it had a key off drain somewhere. Where is the first place to look for this? I have a feeling I may have the alternator hooked up wrong. When I put my signal light on, to turn into the shop driveway, the truck died on me, so there is a definate power loss . I had to boost it just to get er going because there was absolutely no power at the key what so ever. I am going back to work on it tonight and see if I can find the drain, but can you guys maybe give me an idea on where to be looking first?

Also. if the engine doesn't have a ground strap on it, would this cause a drain??

[WRMZ71]

I don't know if no engine ground strap would cause a drain but it shouldn't. I believe if you pull off the negative battery cable then hook a test light between the cable and the battery and if a light comes on then you have a drain somewhere. Start pulling fuses till the light goes out. Once you pull the right fuse you can start troubleshooting that circuit

[Randy70C-10]

Exactly what he said!!

[Longhorn Man]

It's kinda sounding like it isn't charging at all. Get it started and disconnect a battery cable, see if it dies, and if it continues to run, then turn on the headlights with the engine stil disconnected. If it stalls during either of these tests, you need to look at the charging on it. (A volt meter on the battery while running is a better test, but this will wouk if none are avalible)
No ground strap would cause problems, but more of a dim light syndrom over a not running fault.

[68w/sbc406]

i had an electrical scold me for doing the remove the positive battery cable test cause they said it can mess up electronics, i said all i got is a pos deck and a pos tach, i dont care. they didnt have a responce for me then. but i have never had a problem with anything by doing it that way, but i have never done it to a newer car either

[WRMZ71]

People don't like the removing the positive cable trick because the regulator reads through that to tell the alternator how much to charge. If theres no signal the alternator can run full blast and burn itself up. If he jumps it to get it to run and then turns on the turn signal and it kills the engine it might be a completely shelled battery too. I would have the battery tested and start with the easy stuff first. Especially if he knew of a battery drainage problem before all of this.

[Longhorn Man]

I agree that with sensitive electronics, it shouldn't be done. However, I think the HEI is the most advanced electrical component on his truck.
You can pull the pos, or the neg, it makes NO difference. However, if you pull the positive and it bumps the fender, or any other metal, it'll create a burn mark on your hand where it starts to weld it's self to said metal. (Do the neg cable...it's safer)
If you have a properly functioning alt, you can drive your truck all day with no battery in it at all. I have done it, even on an early 80's fuel injected car. (drove 90 miles in an 82 firebird with no battery when it was damaged in a fender bender. Just borrowed a battery to start up with, and then gave it back. I put a thick leather glove over the positive cable end, and zip tied it so it wouldn't fall off, and drove the sucker for the rest of the day.

No, it isn't the ideal way to do things, but, it'll get it done on something like this, and the chances of damage are microscopic.

[71Longbed]

also check for dirty cable ends at the little black box on the fender happned to me wais draining 1.5 volts and my lights were dim as **** and it would shut of or it would signal very slow on the turn signal

[dubie]

ok I am at the shop right now. I fouind out that I had my alternator wired wrong so I followed the step by step in FAQ by toddtheodd and changed that. I had to jump start it to get er goign because the battery was drained. I got her running, put it in gesr, was backing up, turned the headlights on and she went dead. I am searchign for damn test light here to see if it's somewhere else, but got any ideas on the truck dying when I turned the lights on?

[Longhorn Man]

Tim, did you verify that it is actually charging?
You may have fried the alt at one point.

[cableguy0]

yupppp what he^^^^ said. if the alternator was wired wrong i would bet it cooked itself but another thing.if you took your battery totally dead charge it with a charger not the alternator that will burn the alternator up in short order wayyyyyy too much load for it.

[dubie]

OK Just got back from the shop. I got it all wired up, boosted it and took it for a drive with the high beams and every other accesory on. It ran great. I brought it back in the shop and turned it off. Tried to start it again and it's dead. I figure the battery has been run so dead that it needs to be charged. I took it out of the truck and put it on the charger overnight and will try it in the morning

[cableguy0]

another thing when you fully discharge a battery especially one with any age on it thats usually the end of its life

[dubie]

it's a brand new Battery as well, forgot to mention that

[dubie]

Got into work this morning, took the battery off the charger and dropped it inot the truck. I turned the key and she fired right away. I took it for a spin and everything is lookuin good so far. I will let it sit outside all day and try to start it before I go home today and see if it's dead or getting weak. Sure hope I didn't burn the regulator out of it Hoping to get out here sometime tonight or tomorrow and try the test light hing to see if there is a drain some where else. Thanks for all your help guys

[Warbones]

I hope thats what the problem was dubie. I'll be watching this thread to see if that solved the problem.