M998 alternator wiring help

[teteacher101]

1989 M998 6.2 3spd auto

Hello everyone, so I could use some help with getting the wiring figured out on my alternator replacement.

I originally purchased the replacement alternator and kit some years ago and had it in storage until now when the old 60amp has had enough. The box looked like it was dropped from a 747 so who knows if everything was there even, and the directions I got with it might as well be in hieroglyphics. I found some stuff online, but it doesn't seem to address what I have with 100% accuracy.

Here are the harness tag numbers at the alternator:

-Large red terminal, tag# 5A, other end goes to starter terminal
-Small red terminal, tag# 2A
-Old butt connector style push on terminal, tag# 568A, I assume it gets cut off and an eyelet installed?
-Ground, tag# B

So I put the big ground strap on the lower alternator stud, then ground wire tag# B on a bolt location behind the regulator along with a ground wire I ran years ago.

The other wires I don't know which stud they attach too, and the larger 5A is the one I assume gets replaced with the larger wire that came in the kit, but then goes to the starter? Or does that install on one of the smaller studs and the new replacement larger wire goes on the big stud then gets routed down to the battery like I saw in they instructions for the 200amp dual voltage?

Help! Aggggg!

 

[Mogman]

568 gets abandoned (there should be a blind plug in the kit for it, if not tape off the end and tie it back where it cannot short out), 2A goes to the AC terminal, 5A goes to the sense terminal and you will have to run new much larger cable to the battery box from the 28V output and also a lead to a connection between the batteries for the 14V output, good for 25A or so, the install kit should have all the stuff, also the directions are actually pretty clear, read them over a few more times and see if it does not start to make sense.

 

[teteacher101]

Hey thanks so much for the information, it's helped a TON.

Yes, I think the kit was scabbed together as I've gone to the hardware store more times then I can count. The instructions that I had got with it are for a 200 amp dual voltage, I only have a single voltage output (look at my pics in the OP) unless I'm mistaken on something? I do not see anything in the last part of the instructions (I labeled it C in pen) for installation of a 14v wire from the batteries to the alternator and nothing was provided in the kit either.


Thoughts?

 

[Mogman]

Interesting, it does not look like that regulator has a 14V tap, should be the same otherwise, the sense post may also be labeled IGN. that is where the #5 wire goes.

 

[teteacher101]

Interesting, it does not look like that regulator has a 14V tap, should be the same otherwise, the sense post may also be labeled IGN. that is where the #5 wire goes.

No labels on anything, but I did get the wires all routed and installed an I fired it up-no smoke, no fire, and it was charging-so I would say so far so good! Thank you sir!

I might have to change the front bolt for the adjustment bracket to a different style head as the bolt I used appears it might have the belt slap it once in a while and I could use just a little more clearance.

This alternator replacement has just been a complete cluster, looking forward to getting it done then a couple of little things and I'll be posting it for sale. I've had it for 6 years, the kids are getting older and we are just looking to move on, maybe get a side by side or something.

 

[juanprado]

That might be a 100amp alt.
What is the part number?

 

[teteacher101]

No idea? Anything in the pictures of the data tag help you at all?

 

[juanprado]

See if the alt has a part number?

It just looks different to me but could be the picture.
I saw a reference online to a single volt 200amp unit but have never seen one.

 

[Mogman]

That might be a 100amp alt.
What is the part number?

It might be, it does not look as massive as the 200A come to think about it.
I have a 100A on the floor around here somewhere, I thought it used the same dual voltage reg as the 200A

 

[teteacher101]

See if the alt has a part number?

It just looks different to me but could be the picture.
I saw a reference online to a single volt 200amp unit but have never seen one.

Only numbers I seen were the ones on the data plate in the pictures.

 

[juanprado]

Only numbers I seen were the ones on the data plate in the pictures.

In your pics right under the regulator, there is a black data plate curved on the alt body. Can you snap that?

 

[teteacher101]

Oof, I might have to get creative to get in there.

I'll check tonight. Thanks

 

[juanprado]

You can just read it also. Typically it has a part number and a description of the alt.

I am spit balling but I think you have a 100amp and using a 200 amp install kit. Main bracket I think is different. You would have to dig in the tm to see what are the correct pieces/mounting etc and wiring for a 100 amp IMHO

 

[teteacher101]

Numbers are tore up, not sure if you can make anything out here.

 

[Coug]