NEED HELP! I'm beyond aggravated

[mr48chev]

I agree with removing the negative cable and either using a multimeter or test light between it and ground to see if you have something drawing power when it shouldn't.

A blown diode in the alternator will cause a drain. This is usually caused by shorting something in the electrical system and getting a big spark in the process.

As someone said, an alternator that is overcharging will cook a battery in short order.
when running without anything on you should be charging right at 14.2 volts. If it is up around 15 or higher it is overcharging.

Is your alternator charging at all? You may be running on battery only and driving just far enough to run the battery down during your round trip. When you come out the next morning the battery is low enough that it won't crank the engine over.

Do a bit of homework and learn how to test a charging system correctly (it isn't that hard to do it right) rather than trying off the wall suggestions like checking for a spark and risking blowing a diode or worse. I cringe every time I see someone suggest some may or may not work or be correct method of testing electrical items because that's the way uncle Billy showed them on his Model A.

[wwotr]

Originally Posted by lillwr

I'm so angry, I'm about to just post the truck on CL and wipe my hands clean of it. I've only had it for about a month and a half now and already been through 2 batteries. If the truck sits over a weekend as it always does, the batt dies. I have NO accessories hooked up. No radio, dome light, nothing plugged into the lighter thing, NOTHING! Why is my tuck eating batteries? It's just a lil I6 69 C10

Something not mentioned so far and I have mechanical experience dating back to Junior College.

When my 72 GMC did that, I replaced it with an Optima Yellow Top Battery, and it killed it in 2 days.

Soulution: Figured out it was the Horn Relay.
Replaced it and I can let my Truck sit in the Garage for 3 Months without starting/charging it up, and it turns over everytime.

Just a thought.

[tim21391]

heres the problem i had.. if you slapped a new battery in my 72 and let it sit over night it would be dead.. i found out my ignition switch went bad.. i thought that was it.. but then come to find out my hei distributor wire i didnt run one from the fuse box.. i was using the wire from the old points system and it was still getting power to it..

[Irishpilot]

I strongly recommend the internal alt. I got a 94 amp one from the parts store. Just ask for the 86 Camaro 305 HO engine with AC. You get a 94 amp, internally regulated alt with teh V belt pulley. It is awesome, and you get 12 volts at idle.

[lillwr]

It only dies after sitting for a few days. I drive it wed-sat then it sits. When I go out to start it the following wed morning it's dead. I haven't had an opportunity to get a new test light (when I found mine it was broken) so I've just been pulling the neg cable. On a side note, what's the knob/button looking thing on the floor to the left of the brake pedal?

[Todd Hepler]

Originally Posted by lillwr

On a side note, what's the knob/button looking thing on the floor to the left of the brake pedal?

Should be the brights/highbeams

Todd

[mcbassin]

Originally Posted by jay6891

If funds are available, I would also suggest converting/upgrading to a internal regulated alternator. Pretty easily done, and you get rid of the old reg and alt. Think I used one off a Mid eightys Camaro. Been a while ago.
Here is a link for some directions on how to do.

http://67-72chevytrucks.com/vboard/s...d.php?t=119379

I agree with this, get rid of the old school regulator and alternator.

[lillwr]

I have the alternator how-to bookmarked but it'll have to wait for a later date since I'm not currently working. It's definitely something I wanna do.