1948 B1B

[jerryfox]

I really have no clue how to check the system I have done a few things with a meter, but once again not sure what I am looking for.

 The generator is putting out 7 volts. When I check different leads in the regulator they are as follows. Arm to fields read 4 volts, arm & battery read 5.9, field & battery read 6.2. If I disconnect the battery the truck dies.

[ggdad1951]

can you clarify what you are trying to troubleshoot?  Is the truck dying?  Not charging the battery?  Please clarify your problem.

[jerryfox]

not charging the battery

[B1B Keven]

If it's been sitting for a while or you've had the battery disconnected, it probably needs the

voltage regulator 're-polarized'.

I can't remember off the top of my head how to do it  but there is a thread here explaining how.

Just need to do a search.

[B1B Keven]

Found it:

http://p15-d24.com/topic/20297-polarize-your-voltage-regulator/?hl=polarizing#entry195269

[jerryfox]

I watched to video and tried it at the regulator. No luck. Now the other video showing to do it at the generator show how to do it, but he made the statement that the jumper was hooked to a known power source. I am guessing that it comes straight from the battery. Is it hooked to the positive or negative? And is the truck running when I do this?

[Don Coatney]

[jerryfox]

ok. did the battery to gen (arm) still no luck. The wiring in this truck is pretty rough. Should I look at replacing at least the wiring in the charging system?

[Plymouthy Adams]

I would suggest that you use a hand over hand or meter trace of the wiring and follow component tests as outlined in the repair manual to see if your are even capable of charging with said components..this will take but a few minutes and clear up a lot of ifs...be sure to have a schematic for your application on hand..

Edited October 21, 2014 by Plymouthy Adams

[B1B Keven]

Not a bad idea.

Here's a schematic that will help.

http://dodgepilothouseclub.com/know/wiring_harness/wiring.htm

 

If you're interested, here's a place that sells new cloth covered wire:

http://enginebarn.myshopify.com/

 

I cut my harness apart and replaced one wire at a time.

[MBF]

I recently went through this with the 2.5 ton.  Suddenly stopped charging after a long run at night.   Pulled the generator, did the motoring test which it failed, so I tried a a spare generator.  Still nothing.   Rechecked the terminals on the generator and regulator ends, polarized it-no change.  I did notice that the circuit breaker contacts in the regulator were cycling open and closed.  Checked ground on the regulator and cleaned up the contacts-nada.  Swapped in another regulator and voila back in business!