M1031 CUCV Alternator

[KeelanDavis]

So I need to either rebuild or replace my passenger side alternator on my M1031.
Can I still buy an OE Delco-Remy alternator anywhere, or should I just rebuild it. Can anyone recommend a good replacement alternator and a good quality complete rebuild kit? I guess it doesn’t matter if it’s an off-brand if it works, but I’ve heard the non OEM alternators can be very hit or miss. I’m new to the CUCV world and the Forum, if there is already a thread for this then I apologize.

 

[sneekyeye]

Rebuilding them is not particularly hard if you have some tools and are handy. I did both of mine and the only trouble I had was one of the bearings was seized onto the main shaft of the alternator rotor. I bought kits from somebody on this site. I really don't remember who it was, it has been several years at this point.

 

[Guyfang]

I could turn this into a parts wanted thread if you like. Might get you better visibility.

 

[KeelanDavis]

I could turn this into a parts wanted thread if you like. Might get you better visibility.

I would appreciate that if you think it would help. I’m looking for both advice and potentially parts.

 

[KeelanDavis]

Rebuilding them is not particularly hard if you have some tools and are handy. I did both of mine and the only trouble I had was one of the bearings was seized onto the main shaft of the alternator rotor. I bought kits from somebody on this site. I really don't remember who it was, it has been several years at this point.

I’ve rebuilt a few other Delco Remys that came on airplanes, but I wasn’t sure if these CUCV alternators had any specific information I should know about besides the isolated ground. I’d like to get it done by next Saturday, March 2nd. Today is Feb 22nd, so that gives me 8 days. I’m debating on just buying a replacement alternator online and rebuilding the one I have later and just saving it for when I need it.

 

[Guyfang]

Then if you are going to rebuild an alternator, use this thread for info and advice. If you are going to buy parts, or an alternator, start a parts wanted thread. Why? well, first its the rules, but secondly, if you are looking for parts, a parts wanted thread get more visibility. AND, after you get your parts, we can close the thread. Vendors, or people who sell things are not going to look at every thread in the forum. BUT, sure will look at a parts wanted thread. And your info/advice thread can keep on going.

 

[KeelanDavis]

Then if you are going to rebuild an alternator, use this thread for info and advice. If you are going to buy parts, or an alternator, start a parts wanted thread. Why? well, first its the rules, but secondly, if you are looking for parts, a parts wanted thread get more visibility. AND, after you get your parts, we can close the thread. Vendors, or people who sell things are not going to look at every thread in the forum. BUT, sure will look at a parts wanted thread. And your info/advice thread can keep on going.

That’s good to know. I guess keep it in this location so I can gather information, and whether or not I decide to rebuild it will determine if I make a new thread in the parts wanted section. I appreciate your help sir.

 

[KeelanDavis]

I got the alternator out of the box it shipped in and opened it up. It looks like it was wayyy overloaded or it shorted out. Either way, I’m going to order one off of eBay and then have this one rebuilt at a shop. Some of the windings look cooked. I need to figure out what caused this before I put the new one on and potentially cook it too. Does anyone have any ideas?

 

[WWRD99]

Yeah looks like one of the field coils burned up. I wouldn't use that part. Do you have another you could part out to use? I have seen a few of these nos on surplus sites but it isn't that cost effective. That type of damage comes from the diode pack or another internal short like the regulator full fielding.

 

[KeelanDavis]

Yeah looks like one of the field coils burned up. I wouldn't use that part. Do you have another you could part out to use? I have seen a few of these nos on surplus sites but it isn't that cost effective. That type of damage comes from the diode pack or another internal short like the regulator full fielding.

I went ahead and ordered an eBay unit. I might send this one off and have it rebuilt at a shop if it is cost effective to do so. I’m trying to figure out how to wire up the passenger side alternator now because I wasn’t the one to take it off and I bought it without it mounted, so I don’t really know what wires go where.

 

[sneekyeye]

Has it been converted to 12v or is it still 24?

 

[KeelanDavis]

Has it been converted to 12v or is it still 24?

The batteries are still in series so I assume the whole system is still 24v.

 

[KeelanDavis]

My eBay alternator came in and it doesn’t have this little capacitor. Does anyone know how to test one and see if it’s any good? I swapped the spacer, fan and pulley onto the new alternator already.

 

[WWRD99]

My eBay alternator came in and it doesn’t have this little capacitor. Does anyone know how to test one and see if it’s any good? I swapped the spacer, fan and pulley onto the new alternator already. View attachment 917746

You don't need it. That's for radio interference of a rt524 that the military would use in the back. If you end up getting a radio then you can pop a new one on it.

Sent from my SM-S906U using Tapatalk

 

[KeelanDavis]

You don't need it. That's for radio interference of a rt524 that the military would use in the back. If you end up getting a radio then you can pop a new one on it.

Sent from my SM-S906U using Tapatalk

Okay, sweet! Thank you for the quick response I really appreciate it! Can you possibly direct me towards a wiring diagram so I can go through everything on the truck side before I install this alternator?

 

[WWRD99]

Okay, sweet! Thank you for the quick response I really appreciate it! Can you possibly direct me towards a wiring diagram so I can go through everything on the truck side before I install this alternator?

There should be some easy ones in the tm section in the sticky of this section. Don't use a civi harness pics...they won't be right.

Sent from my SM-S906U using Tapatalk

 

[KeelanDavis]

Is this little orange wire necessary? I think it goes to the diagnostics system. Mine is frayed off next to the fusible link, and I’m wondering whether I should replace it or just cut it off and cap it.

 

[adf5565]

Is this little orange wire necessary? I think it goes to the diagnostics system. Mine is frayed off next to the fusible link, and I’m wondering whether I should replace it or just cut it off and cap it.
View attachment 917810

I would double check to confirm it is the diagnostic circuit (which I'm pretty sure it is) but if so you can remove/cap it. I removed the entire diagnostic circuit from my m1008.

 

[KeelanDavis]

I would double check to confirm it is the diagnostic circuit (which I'm pretty sure it is) but if so you can remove/cap it. I removed the entire diagnostic circuit from my m1008.

I checked the wiring diagram for the diagnostic system and it was on there. I just want to make sure it won’t fry something if I don’t plug it in. Thank you for your help!

 

[KeelanDavis]

Turns out you don’t need that little orange wire. The eBay alternator is working. Getting about 28.5v across both batteries. Nothing has caught on fire yet.