Gen 1 ???'s again-alt charging

[M1008driver]

So last night I was driving down the highway thinking how good my M1008 was running when the Gen 1 light came on. There was freezing rain and the defrost was blowing full blast.

Please tell me what you recommend...

I have two CUCV Electric rebuild kits in my garage. I want a spare alternator and that is why I have been waiting to rebuild mine, even though this is the first real problem.

I checked the batteries using my multimeter with the engine off and running and the battery is charging. How to Test CUCV Alternators | eHow.com

I tried to troubleshoot per the TM's but I can't get connection loose from the alternator. I know it has a pin holding it in but the bracket is in the way making it hard to get to and I did not want to break the plastic connection

The belts are good and tight.

So I am thinking since I want a spare alternator to either buy the AutoZone DL7157 for the driver's side or the NAPA Wilson 90014277 (making sure it has the isolated ground).

This way I could rebuild my CUCV alt and always have a spare as they seem hard to find. What way should I go?

My other question is it OK to wait since my alt is still charging. Money is kind of tight this month.

EDIT- The AutoZone alt has a lifetime warranty and military discount. The NAPA alt warranty is 12 mos.

 

[M1008driver]

I did check the heater fuse and it is new and tight. I cleaned connections too. The Gen 1 light is dim and gets brighter when I run the heater or at higher rpm's.

 

[Dr.Jay]

I am going to suggest that you check the ground wire for the heater blower motor, and be sure the connection is clean, and tight.

How many volts did you have at the red battery terminal at the back of GEN 1 with the engine running?

 

[M1008driver]

How many volts did you have at the red battery terminal at the back of GEN 1 with the engine running?

14.12 volts

I am going to suggest that you check the ground wire for the heater blower motor, and be sure the connection is clean, and tight.

Could you save me allot of time and tell me where this is? I am searching the TM's, but haven't found the ground yet. I know the blower is behind the 2nd battery and I did not see anything that looked like a ground.

I did find this and have no clue what it is. The part with tape was on the POS 24 Volt junction bar and the fusible link looking thing was on the NEG junction bar.

 

[M1008driver]

Nevermind on the unknown part. I did a search and found it. Now to find the ground...

http://www.steelsoldiers.com/cucv/15777-capacitor-assembly.html

I found this, but the ground eludes me. I even did a search where it was said the heater system is so simple. Any help will be appreciated. I spent the afternoon on this problem with not much luck. I could have bought an alternator and changed it faster.

 

[Dr.Jay]

Nevermind on the unknown part. I did a search and found it. Now to find the ground...

http://www.steelsoldiers.com/cucv/15777-capacitor-assembly.html

I found this, but the ground eludes me. I even did a search where it was said the heater system is so simple. Any help will be appreciated. I spent the afternoon on this problem with not much luck. I could have bought an alternator and changed it faster.

I apologize for giving you the incorrect information about the ground wire.

The blower motor is grounded through the motor case to the fire wall. There is no wire. My M1009 has a 14 gauge ground strap that is attached to one of the blower motor mounting screws, then fastened to the firewall with a sheet metal screw. It does not appear to be factory.
Again I apologize.
It does not appear to be factory

 

[M1008driver]

Thanks anyway. At least I learned something about my truck. So many people just say did you check the ground. I did remove my dash cover and clean everything too. Now my heater blower is quieter and still works.

I think I will just keep an eye on the alternator and buy the AutoZone one. It has a lifetime warranty with military discount and will let me rebuild the original for a spare.

 

[Dr.Jay]

Have you disconnected your batteries, and tested the voltage for each one without the engine running. You should have a minimum of 12.5 volts for each battery.

With the engine running as you increase engine RPM does the voltage output for Gen 1 increase?
Do your batteries discharge overnight? ( indicates a failed Diode Trio in the alternator)
What condition is the Gen 1 fuseable link at the junction block? Is the insulation melted?

 

[stampy]

Best to go through the cable connections and clean them with fine sandpaper till they shine same with fuse legs, and fuse block. I started at the batteries and then the fuses/block. all my electrical gremlins went away. I don't even have the glow on gen 1 when pulling a load such as lights and the fan and the radio now. If this does not take care of the issue you either have a generator going bad or a fan pulling a heavier load than normal. If the outside air intake was covered with ice this may happen also, I would think.

 

[M1008driver]

Have you disconnected your batteries, and tested the voltage for each one without the engine running. You should have a minimum of 12.5 volts for each battery.

Yes

With the engine running as you increase engine RPM does the voltage output for Gen 1 increase?

Yes

Do your batteries discharge overnight? ( indicates a failed Diode Trio in the alternator) What condition is the Gen 1 fuseable link at the junction block? Is the insulation melted?

No and the fusible link is good.

Best to go through the cable connections and clean them with fine sandpaper till they shine same with fuse legs, and fuse block. I started at the batteries and then the fuses/block. all my electrical gremlins went away. I don't even have the glow on gen 1 when pulling a load such as lights and the fan and the radio now.

I did that several months ago and this problem is new to me. It seemed to work for awhile. It seems I need an alt rebuild. I was planning on doing that someday anyway.

 

[Dr.Jay]

Thanks anyway. At least I learned something about my truck. So many people just say did you check the ground. I did remove my dash cover and clean everything too. Now my heater blower is quieter and still works.

I think I will just keep an eye on the alternator and buy the AutoZone one. It has a lifetime warranty with military discount and will let me rebuild the original for a spare.

The alternators are fairly simple to rebuild. I get my parts locally.

If I go with a new unit, the alternator has 95% of the same internal components as one for a 1978 Cadillac Deville with multi port fuel injection.

The difference is the rear case, and the isolated ground terminal is missing. All of the other components are the same.
(I add the terminal myself by drilling a hole in the case, and using a long 1/4 inch carriage bolt, and lexan isolator washers that I make using a hole saw.)

The whole alternator costs only $75 plus the core $15 at O'reillys : Part # : 01-0136X
15 minutes of my time, and a couple of cents for a bolt, and some plastic washers

 

[Warthog]

The heater fan and the GEN1 exciter circuit share the same fuse.

If your heater fan switch is old and dirty, it will draw a higher amperage .

This causes the GEN1 light to come on.

Replace the blower switch as it is more than likely the original switch.

Report back your results.

 

[M1008driver]

OK, but I need to do some searching first to understand what I am doing.

EDIT- You have got to be kidding me. I found the switch. I do have a new radio to install and will probably do it at that time. Thanks!

http://www.steelsoldiers.com/cucv/83826-blower-motor-switch-not-working.html

 

[M1008driver]

So once I get the instrument panel cover off is there really only four screws holding the heater controls in? ( I can't go into combat without a plan)

 

[Warthog]

four screws for the main plate and a couple on the switch itself (iirc).

 

[M1008driver]

You are the best! After doghead of course...

 

[M1008driver]

Reporting back. I bought the blower control switch at Oreilly's for $10.99 and replaced my old switch. I did find the elusive ground and it looked like it was not used on purpose.

I tested the ground, and grounded or not grounded had no effect on the light. The switch did. My GEN 1 light is dim and gets brighter when I accelerate. It also gets brighter each click of the switch. I could tell the new switch did make a difference, just not fix my light problem.

So what next? I think I need a rebuilt alt...

 

[M1008driver]

Today I changed the heater fuse even though my old fuse looked good. Now at idle the light is out and gets brighter with acceleration or using the blower fan switch. When I get time I am going to make a dedicated ground to the heater control unit just in case.

I really think if the diode trio was going out I would hear a noise and I don't. I am still leaning toward an alternator even though mine is charging.

EDIT- I guess that's it then. The silence tells me to replace or rebuild the alt. I think I am going with the DL7157 and mark it DS side only, rebuild the original and keep it for a spare. I have new belts to install anyway.

 

[M1008driver]

I cleaned and sanded all the things connected to the 12 volt junction. My light is out and flickers when I accelerate or comes on with the heater fan. I have my new radio and will make a better ground for the heater unit at the same time, probably this weekend.

I am still planning on buying an alternator. I just don't know if I want the AutoZone DL7157, Wilson Delco Remy, or one from EBAY. AutoZone is cheaper but DS only.

EDIT- Any complaints about the Rare Electrical alt? They say they are new.

 

[mudman]

You are the best! After doghead of course...

Yea..!! Dog head is Cool... Warthog is.......Well........aaaaaaaaah.......huuuuuuum!! Never mind!!!