Electrical gremlins

[Anvilface]

I swear, if it isn't one thing, its another.

I had an alternator that was only putting out 22.9 volts, tried to adjust the regulator, no joy.

Swapped regulators, no joy.

Brand new alternator, 28.2 volts...yay! But then..

Drive em around for about an hour today. While headed back to the yard, the guard goes from solid green range to flat dead. Truck ran fine, headlights strong, cut her off and tried to restart. Batteries flat dead. I'm thinking one of the battery connections vibrated loose while driving, but I didn't have the opportunity to test anything today.

Bout to drive me bananas, not sure which is worse, electrical problems or air problems.

 

[74M35A2]

 

[porkysplace]

I swear, if it isn't one thing, its another.

I had an alternator that was only putting out 22.9 volts, tried to adjust the regulator, no joy.

Swapped regulators, no joy.

Brand new alternator, 28.2 volts...yay! But then..

Drive em around for about an hour today. While headed back to the yard, the guard goes from solid green range to flat dead. Truck ran fine, headlights strong, cut her off and tried to restart. Batteries flat dead. I'm thinking one of the battery connections vibrated loose while driving, but I didn't have the opportunity to test anything today.

Bout to drive me bananas, not sure which is worse, electrical problems or air problems.

Air is easy you can hear it most of the time.

 

[74M35A2]

You can hear electricity sometimes too. Like when I dropped a ratchet and it wedged between the starter solenoid terminal and oil filter, and my truck caught fire.

 

[Anvilface]

You can hear electricity sometimes too. Like when I dropped a ratchet and it wedged between the starter solenoid terminal and oil filter, and my truck caught fire.

lol, done that, on an MK48...years ago. Across the top of the batteries though. I was able to kick it loose before the batteries exploded. Mighty scary though.

 

[Anvilface]

Air is easy you can hear it most of the time.

yep, when you are losing. We you just aren't getting any air. That can get rough.

 

[juanprado]

Did you test the batteries before you replaced the alt?

I have a feeling you had multiple issues with bad batteries being one. If you had bad batteries, put in a new alt, the old batteries have released the magic smoke.....

 

[Anvilface]

Yep, I believe you are correct. I checked the batteries..not even under any load yet. Just voltage....#1 =13.4V, #2 =11.2V, #3 =6.5V, #4 =4.2 volts....I think I've got one, and possibly two batteries that are hashed. I might just eliminate the two bad ones and run a two battery set up for awhile. It doesn't get that cold here anytime and it's warming up quickly...probably a temporary as I would rather have 4 in, but run two for now.

 

[Anvilface]

Ok, so I had a bad wire running from battery to battery. I replaced the two weak batteries and BAMM...she started right up. But NOW the gauges are gone wonky. Voltage, fuel, oil pressure...all electrically operated gauges started jumping around and then flat lined. Alternator still putting out 28.2 volts...all other systems seem normal...time to break out the dang TM...

 

[wheelspinner]

Yep, I believe you are correct. I checked the batteries..not even under any load yet. Just voltage....#1 =13.4V, #2 =11.2V, #3 =6.5V, #4 =4.2 volts....I think I've got one, and possibly two batteries that are hashed. I might just eliminate the two bad ones and run a two battery set up for awhile. It doesn't get that cold here anytime and it's warming up quickly...probably a temporary as I would rather have 4 in, but run two for now.

I have run two batteries for years. Both here and in NY. 923 and LMTV both. Never had an issue.

 

[74M35A2]

Sounds like the dash power solenoid in your PCB is tired. Common at this age. Flip the battery switch several times on-off-on before starting to see if it clears up. If so, that is likely it. Battery voltage should be 12.8v each or close, even 12.0V is only 20% charged. Don't quantify their health by whether they start the truck or not, even though that is obviously important and pretty much their only job.