Alternator 1 not getting excited

[Mohawk Dave]

Ok, I read all the Gen 1 threads. But I need some clarification.

My Gen 1 light stays on. My heater usually makes the fuse blow. I checked grounds, must be a shorted blower motor like in the other thread.

I bought two rebuild kits from ASP, rebuilt the alternators today. I get 23/24 from Gen 2, and about 11 from Gen 1.

It is as if Gen 1 is not getting excited. I printed out the wiring diagram from the other thread and started chasing, but did not find the problem.

Warthog, Doghead, any others, where do I need to look for this problem?

Brandnew batteries btw.

Thanks in advance,

Dave

 

[PropDr]

I'm going to assume it has a delco 12si alternator or something similar. If you have battery voltage @ pin one on the harness side of the alternator connection with the key in the run position you have excite power and that is not the problem. Did you ohm out the field winding while you had it apart? Sounds like it could be open, have a bad connection between the brushes and slip rings or a bum regulator. I would start by tearing it down and checking all of the alternators internal connections and ohming out the filed to chek for a open circuit. Is it possible that they gave you a 2 24v regulators instead of 1 12v and one 24v?

 

[Mohawk Dave]

PropDr,

It is possible they could have given me two 24v regs. I did not ohm the windings whilr I had it apart. The alternator looks very new also. (Which I know don't mean Jack) I put all new parts in them. THey are Delco 27si. New regulators, capacitors, brushes, the whole kit and kaboodle.

I will check the internals tomorrow. I see you're in Riverside. I'll be in Redlands. Is it possible you will be around, and have time to take a look at it if I drive to you?

Thanks,

Dave

 

[PropDr]

Sure, I don't see why not.

 

[Mohawk Dave]

Thanks, I'll PM you right now with my number.

-Dave

 

[usmc320]

Try rubbing it.

 

[Warthog]

Pull the 2 pin plug at the alternator. Clean the terminals. They are usually caked with dried grease that interfers with the contacts.

Check for voltage at the red and brown wire. constant voltage at the red wire and voltage at the brown wire with the key is run positiion only.

With the key off, check for voltage at the big red wire.

Double check/clean both ends of the big black ground wire

Disconnect the orange wire from the heater until you can figure out why the fuse keeps blowing

What kit number did you get from ASP?

 

[R Racing]

blow kisses at it !! lol

 

[Warthog]

I'm going to assume it has a delco 12si alternator or something similar. ?

The CUCV alternators are 27si type 100 alternators with an isolated ground modification. They are 12v alternators.

 

[ssgtcampbell77]

Ok, I read all the Gen 1 threads. But I need some clarification.

My Gen 1 light stays on. My heater usually makes the fuse blow. I checked grounds, must be a shorted blower motor like in the other thread.

I bought two rebuild kits from ASP, rebuilt the alternators today. I get 23/24 from Gen 2, and about 11 from Gen 1.

It is as if Gen 1 is not getting excited. I printed out the wiring diagram from the other thread and started chasing, but did not find the problem.

Warthog, Doghead, any others, where do I need to look for this problem?

Brandnew batteries btw.

Thanks in advance,

Dave

What does ASP stand for? Im looking for rebuild kits.

 

[Warthog]

One source for the kits has been listed many times. I beleiive it might be in the "glovebox" manual.

They used to be called Spring Hill Auto Electric.

 

[mistaken1]

Is it possible that they gave you a 2 24v regulators instead of 1 12v and one 24v?

I thought the stock alternators were standard 12V isolated ground units that could be swapped from side to side without issue not one 12V and one 24V.

 

[Barrman]

Correct, they are matched 12 volt isolated ground Delco 27si units. They can be mounted on either side if they are both up to stock specs.

 

[Mohawk Dave]

Pull the 2 pin plug at the alternator. Clean the terminals. They are usually caked with dried grease that interfers with the contacts.

Check for voltage at the red and brown wire. constant voltage at the red wire and voltage at the brown wire with the key is run positiion only.

With the key off, check for voltage at the big red wire.

Double check/clean both ends of the big black ground wire

Disconnect the orange wire from the heater until you can figure out why the fuse keeps blowing

What kit number did you get from ASP?

Warthog,

Thanks, I will do this. I bought the 27si heavy duty repair kit. I called ASP and spoke to Steve, told him I had the MV 6.2 and he said, "Yea, a lot of the guys from SS buy from me," I told him that's where I learned about him. Nice guy.

Here's the link for you and SsgtCampbell77's question.

High Output Alternators - Alternator Parts - Starter Parts - Repair kits - DELCO 27SI HEAVY DUTY REPAIR KIT

Thanks again,

Dave

 

[PropDr]

The CUCV alternators are 27si type 100 alternators with an isolated ground modification. They are 12v alternators.

Its the same family as the 12si. The internals are darn near identical.

 

[AndrewH]

Alternators

The hard parts are available thru carquest or auto zone ect. The internals are mounted and wired so as to isolate them. I had to learn this the hard way, meaning I cracked it open and went looking for the individual parts and didnt tell them what they were in. AndrewH

 

[ssgtcampbell77]

Warthog,

Thanks, I will do this. I bought the 27si heavy duty repair kit. I called ASP and spoke to Steve, told him I had the MV 6.2 and he said, "Yea, a lot of the guys from SS buy from me," I told him that's where I learned about him. Nice guy.

Here's the link for you and SsgtCampbell77's question.

High Output Alternators - Alternator Parts - Starter Parts - Repair kits - DELCO 27SI HEAVY DUTY REPAIR KIT

Thanks again,

Dave

Dave, not to be a kiss ass but you should apply to be a moderator here. I think you and Warthog have helped me more than any other members.........ok, 1stSarge draws awesome pictures........anyhow thanks for that link.