Intermittent Alt 1 light

Matt S

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I'm not sure if I have an issue or one developing.

I have an Alt 1 light that sometimes doesn't light when I start the truck.

I've had the dash off and cleaned the contracts with an eraser for the plug and connection to the lamps. I've cleaned the lamp plug also. I believe the contacts to be good. The bulb is good.

I cleaned the ground on the driver's alternator.

The front battery is charging between 14.0v to 14.1v. The rear battery is 14.3v to 14.4v. I can hear the belts squeal when the glow plugs cycle. The gauge is normally where it shows it's charging. Batteries are about 1 yr old.

Is this a problem that's forming in that the alternator is beginning to die or am I missing something?
 

DeadParrot

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If you haven't already, check and clean the two wire plug to the alternator. The brown wire of the pair is the one that goes back to the Alt light in the cluster. Use care, the red wire of the pair is the voltage sense wire and should be hot even when disconnected from the alternator.
 

Matt S

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I swapped the bulb but no change. Sometimes it comes on and other times it doesn't. I'll look for that wire next.
 

cucvmule

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Matt S look at the drivers side alternator and check to see if the charging post, red wire is tight and post does not spin and insulator is complete, not broken. Same with black post, isolated ground, check alternator and ground strap to intake bolt. Simple to check out, if you turn key and it is out sometimes just moving the wires will also make contact. One step at a time.
 

Matt S

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Matt S look at the drivers side alternator and check to see if the charging post, red wire is tight and post does not spin and insulator is complete, not broken. Same with black post, isolated ground, check alternator and ground strap to intake bolt. Simple to check out, if you turn key and it is out sometimes just moving the wires will also make contact. One step at a time.
UPDATE

I went through the steps above. The posts were tight. I removed and cleaned the ground with sand paper. The red wire was tight and clean.
I've been driving it daily due to a broken foot and this is the only vehicle I own without a clutch. It works more often than it doesn't but it will still not light up sometimes.

I'm almost thinking it's on the way out. That belt squeals when the glow plugs are on. I think I saw in another post this could be a sign the alt is getting tired or the belt is loose. I've tightened the belt.
 

cucvrus

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An alternator shop can bench test that alternator if you remove it. Many times the light issues are internal to the alternator. Good Luck. Have a Great Day and Be Safe.
 

dependable

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Loose belt can creep up on you, that's for sure, and is often the cause of intermittent alternator. If your still having problems, maybe try replacing or rebuilding alternator. The only alternators I've seen that were intermittent though were a batch of surplus govt rebuilds I bought that turned out to have been rebuilt with substandard fasteners. The alternator internal assembly screws were new, but too short.
 

Matt S

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So my Alt 1 threw a belt on the highway this morning. The alternator has been intermittent with the light coming on at start and not working. While the pulley still turns, I'm thinking of getting a rebuild kit and a new set of belts for the entire truck.

Does anyone know what kit to get for the alternator? I've seen some of the links and sites but they come with different parts and I'm not certain which one to get. I PM'd the gentleman on the this site that has sold kits over a month ago and not heard back from him.
 

cucvmule

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Matt S Have you checked out the CUCV Helpful Threads?

Lots of great information. There is a member here that has a lot of the rebuild parts.
His handle will come up, if I can remember.
 

Matt S

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Matt S Have you checked out the CUCV Helpful Threads?

Lots of great information. There is a member here that has a lot of the rebuild parts.
His handle will come up, if I can remember.
Yes I have. The links to the kits don't work. The other links lead to multiple kits. Tow4 is the member I PM'd over a month ago and haven't heard back from.

Which kit/parts are necessary?
 

Matt S

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Update - I've contacted 2 vendors. Kits look similar but one includes the hardware and other one does not. I'm placing an order and I'll update with the results.
 

Tow4

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Yes I have. The links to the kits don't work. The other links lead to multiple kits. Tow4 is the member I PM'd over a month ago and haven't heard back from.

Which kit/parts are necessary?
Sorry I missed your pm Matt. I had replied to several inquiries and thought I got all of them. I'm not offering the kits at this time. I may in the future and will post another classified ad at that time.
 

Matt S

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Well...It was going well and then the rear bearing didn't want to come out and the housing is toast.

Now I'm looking for a new one. I hate it when I do that.
 

dependable

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When I "rebuild" my alts, I usually do not replace the bearings if they seem tight and are running quiet. Usually they are not the problem, especially on relatively low mile CUCVs and the OEM ones are probably better than the reproductions.
 

Barrman

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It reads like you have a broken foot, need to drive your CUCV to work and now it can't be driven because your alternator rear housing is broken. Correct?

Put your passenger side alternator on the drivers side, wire it up and isolate the wires that went to the passenger side alternator so they don't touch anything. You are in California where you won't have to do repeated super cold starts. You can get 10-15 starts on good batteries without working alternators. Get yourself to work and back and then charge the rear battery at home each night. This will let you get along until you find another Delco 27Si alternator housing.
 

Matt S

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Los Angeles, CA
It reads like you have a broken foot, need to drive your CUCV to work and now it can't be driven because your alternator rear housing is broken. Correct?

Put your passenger side alternator on the drivers side, wire it up and isolate the wires that went to the passenger side alternator so they don't touch anything. You are in California where you won't have to do repeated super cold starts. You can get 10-15 starts on good batteries without working alternators. Get yourself to work and back and then charge the rear battery at home each night. This will let you get along until you find another Delco 27Si alternator housing.
Awesome and thoughtful response! The foot has healed enough to get back on the motorcycle. That's a great way to get by that I wasn't aware of. The new alternator should arrive this week and I could be back up and running this weekend.
 

Barrman

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Drivers side alternator charges the front battery and keeps the truck running. Passenger side alternator charges the rear battery and is only used for a stock starter motor and stock glow plug system. If your truck starts up like it should. Less than a second of cranking time. Then that back battery doesn't need more than a few minutes of charge before it is topped off again.

Glad the foot is healed enough to be in the wind again.
 

Matt S

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The new alternator is on. The gauge initially went to the high end of the gauge. Might've been since it was catching the battery back up to par. It was charging at 14.48v while Alt 2 was 14.40v. After a drive the gauge has come down a bit. The dash light has been consistently on.

The new belts are silent. I'm thinking of trying to get another alternator back to get a back up ready.
 
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