checking alternators

[ktm25089]

Hello,
i;m in progress restoring one for a friend.The car had to start for 6 years.After a all fluid change it started again.Gen1 lamp keep light.gen2 light i think its burnt.The questions are simple and silly but please help me.I have made a search but i confused a little.
they are 2 generators.12v each?
they are 2 batteries charged individual from each generator.?how to measure if the gens are ok?except for the lamps inside because i dont if they are working.
in my M38A1 i have 27,5v on batteries.I can measure 24 on these.is that correct or to check something?
glow plugs are 12v.They are taking 24v and dropped to 12 after the big resistors on firewall.correct?
what else is 12v on the car?
where is the glow plug controller hidden?


Thank you
sorry for the stupid questions
George

 

[cpf240]

1) yes, both alts are 12v, but they are isolated ground, as gen 2 gets its ground reference from gen 1.

2) Gen 1 ( left side ) charges the front battery. Gen 2 puts out 24v across both batteries. Download the TMs, there are some good troubleshooting guides in them.

?) Glow plugs are 12v. The combination of the resistance of the resistor bank on the firewall and the resistance of the glow plugs drops the 24v to 12v for the glow plugs. Look into doing the 12v bypass to avoid a cascade failure of the glow plugs.

?) All of the truck is 12v except the glow plugs, starter and the slave jump connector.

?) The glow plug controller is located under the dash near the steering column / pedal assembly in a small box, usually swinging by its cable.

Please read the CUCV FAQ for answers to many of your questions, and take a look at the troubleshooting guides in the TMs.

 

[Warthog]

Here is a good thread

http://www.steelsoldiers.com/cucv/54292-cucv-alternator-symptoms-diagnosis-fix.html

 

[mistaken1]

2) Gen 1 ( left side ) charges the front battery. Gen 2 puts out 24v across both batteries. Download the TMs, there are some good troubleshooting guides in them.

Gen2 puts out 12V (nominal) across the back battery only. The fact that the batteries and alternators are connected in series results in 24V (nominal) from the vehicle chassis (front battery negative) to the back battery positive.

Each 12V battery is charged independently by a 12V alternator.

 

[Warthog]

Just to clarify,

Yes, each battery and each alternator are 12v. The drivers side GEN1 charges the front battery and the passenger GEN2 charges the back battery.


Here is a trivial bit of information.

The way they are hooked up, and under ideal conditions where each battery is at an identical state of charge ( doesn't happen hardly if ever), GEN2, with the help of GEN1, will charge both batteries at 24v

This was documented by Amphi a couple of years ago for the Military Vehicle Magazine, Aug 2010 issue.