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-   -   Electrical demon! help appreciated (https://67-72chevytrucks.com/vboard/showthread.php?t=666416)

Russ_the_truck79 04-07-2015 09:56 PM

Electrical demon! help appreciated
 
so about a month ago I pulled up to a stop sign and took a right the truck just died... the only thing that worked was the left turn signal which i didn't even turn on! I took the key out and fiddled with the turn signal switch but the thing kept blinking! nothing else worked the truck would not turn over or make an electrical clicking noise or anything, even the seat belt buzzer didn't have enough power to make a noise. All connections were good as far as I knew. (I tightened up the battery to starter connection the night before as it was loose+no fuses were melted) Had to pop start it and I drove home (about 20 miles and plenty of stop signs) no problem...

I haven't had anymore problems since until last night when I shut my truck off at the drive through window. The truck was warmed up and the gauge said the battery had good voltage but the truck could only turn over once and very very slowly when I attempted to start it not 2 minutes later! Since this is my dd I am very hesitant to drive it now... I'm not sure if the problems are related or not but Please help!

BTW I recharged the battery after the first incident using a charger and an extra battery in a way that supposedly would refresh a battery that wasn't truly charged The charger said it was fully charged but it couldn't turn the engine over. After using that special charging method the battery worked and continued to work very well.

Thanks for reading I know that was long...
__________________

greg64 04-07-2015 11:16 PM

Re: Electrical demon! help appreciated
 
When you next have the truck running, can you check the voltage across the battery with a meter? It should read about 14.4V, certainly not less then 13. If it's lower, you've got alternator or alternator wiring problems. I'd start there.

wilkin250r 04-07-2015 11:21 PM

Re: Electrical demon! help appreciated
 
The first problem is very bizarre.

The second problem has a few likely causes, neither of which would be related to the first problem, so for now I would just assume them to be unconnected.

A bad battery can often test as "good" by a normal multimeter (or charger) until you put a load on it. It will often show a proper 13.5 volts, but it doesn't have the muscle to back it up.

A bad battery connection can often show up the exact same way, the connection is corroded, and will pass a small amount of electricity through just fine (and read correct on the meter that's on your dashboard), but when you try to pass large amounts of electricity (like starting), that corroded connection holds it back. Imagine moving through water waste deep, walking slowly is fine, but try to move fast and it won't let you.

Russ_the_truck79 06-05-2015 03:47 PM

Re: Electrical demon! help appreciated
 
update: I finally got my alternator tested at autozone and apparently it is in good working order... I have yet to test battery voltage. for the past two weeks it has been fine until yesterday I was driving it, parked it, and 5 minutes later attempted to start it and the battery didn't have enough juice to turn over the engine once. the voltage gauge has been reading 11-13 volts just depending on the day and when it wouldn't start it read 8...

Russ_the_truck79 06-05-2015 03:49 PM

Re: Electrical demon! help appreciated
 
also... I checked my connections to and from the alternator and all the wiring appeared to have solid connections

68c10airstream 06-05-2015 04:56 PM

Re: Electrical demon! help appreciated
 
As a past ASE master mechanic of 30 plus years go over every ground on the truck (the forgotten circuit). I know 67-72 grounds well and I suspect your body style to be close. Remove every ground that you can find, shine up the eyelets and bolts and remove paint from the surface and reinstall,. Start at the block, Rh inner fender to frame??, valve cover(s) braided straps to firewall, and possibly frame rail to box??. The most important connections are at the battery. If your battery clamps have 2 bolts pinching the cable to the clamp throw your battery cables away and buy good brand usa made cables (standard motor products) that have molded ends. What I mean by this is the cable insulation is molded into the lead battery clamp. Air shouldn't be able to get at the copper strands inside the cable. I could fill a dumpster the number of cables I have thrown away from the TEMPORARY EMERGENCY BATTERY CLAMPS THAT USE 2 BOLTS TO PINCH THE CABLE after you strip the insulation. They are temporary use to get you by until proper replacement. Enough of my rant but electrical and drivability problems were my specialty, Good luck, Brian F.

greg64 06-05-2015 08:52 PM

Re: Electrical demon! help appreciated
 
I agree with you, Brian, those 2 bolt battery clamps are junk. When I redid my Suburban, I went nuts with the ground straps. Have yet to have an electrical problem :)

68c10airstream 06-05-2015 10:48 PM

Re: Electrical demon! help appreciated
 
Well put greg. Living in the salt belt as vehicles age my first electrical check is to do what i call a ground sweep. The 12volts + side are usually protected very good but the grounds hang out there with the road salt!!

hatzie 06-05-2015 11:25 PM

Re: Electrical demon! help appreciated
 
Go to Harbor Freight and get a Battery Load Tester. They're on sale for $21. This won't be the last time you use it.
http://www.harborfreight.com/100-amp...9888-9193.html
Clamp on the leads and if the battery reads 12v on the meter bump it to test for 10 seconds and then read the battery volts. If she reads low now replace the battery.
If it reads OK go through the engine bay and rehab the ground straps like airstream said...

motornut 06-06-2015 08:12 AM

Re: Electrical demon! help appreciated
 
I had a similar prob after my batt got stolen during the winter.
They cut the batt cable, faster I guess.
I used those temp battery clamps to get it running
Turns out the cable was pulled up against the bottom of the manifold.
Burnt the insulation, got corroded.
I was replacing the cable when I saw the burn.
Make sure the starter is not drawing too much.

mattcrp1 06-06-2015 09:56 AM

Re: Electrical demon! help appreciated
 
Quote:

Originally Posted by 68c10airstream (Post 7199549)
As a past ASE master mechanic of 30 plus years go over every ground on the truck (the forgotten circuit). I know 67-72 grounds well and I suspect your body style to be close. Remove every ground that you can find, shine up the eyelets and bolts and remove paint from the surface and reinstall,. Start at the block, Rh inner fender to frame??, valve cover(s) braided straps to firewall, and possibly frame rail to box??. The most important connections are at the battery. If your battery clamps have 2 bolts pinching the cable to the clamp throw your battery cables away and buy good brand usa made cables (standard motor products) that have molded ends. What I mean by this is the cable insulation is molded into the lead battery clamp. Air shouldn't be able to get at the copper strands inside the cable. I could fill a dumpster the number of cables I have thrown away from the TEMPORARY EMERGENCY BATTERY CLAMPS THAT USE 2 BOLTS TO PINCH THE CABLE after you strip the insulation. They are temporary use to get you by until proper replacement. Enough of my rant but electrical and drivability problems were my specialty, Good luck, Brian F.

This sounds like the area you need to look. A voltage drop test will tell you for sure, sounds like battery cables.


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