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which alternator so m1008?

muddybuddy

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we are converting protechk5's m1008 to 12volt, and at the parts store we cant find the right alternator with the right built in bracket things. what are you guys using? i looked it up for a regular 6.2, and it still wouldnt give us an alternator that had the brackets:confused: what alternator are you guys running?
 
its the std. 100amp GM large-frame alternator body. the alts that are on the m1008 ARE 12Volt!!!!! the are just charging two seperate 12v circuits (I can explain in more detail, but it get confusing if you dont have the wiring schematics in front of you) Just pull one alt. and run the other to the big bus bar on the firewall. then bypass the resistor on the firewall for the glow plugs. wire the batteries in parellel, the only part that you need to buy is the 12v starter (get a gear reduction unit, they are much better)
 
if you need to get another alt. you will have to clock (spin) the rear half of the case to get the mounting holes to align.
 
im aware that the alternator is 12volt, but we cant find the right alternator that has the same holes as the once we pulled off the truck, the holes are different. all the alternators in the computer for the 6.2 that we looked up were the same ones as the 350, with different holes. do you have a part number we can go off of?
 
Got any pics of the holes your talking about? My CUCV is under a foot of snow and its 17 deg outside... I'm not feeling motivated to run out and look at it up close :haha: I don't remember seeing anything unusual on my truck though when I've worked on it. The Alternators look like they have the same case as all the other 350 and 6.2L trucks I've owned with the only difference being the ground isolation terminal. When converting to 12V you can change to the more common 6.2L alternators and eliminate the ground isolation part of the system.

Read those instructions above a little closer and it tells you some more about it.
 
muddybuddy said:
im aware that the alternator is 12volt, but we cant find the right alternator that has the same holes as the once we pulled off the truck, the holes are different. all the alternators in the computer for the 6.2 that we looked up were the same ones as the 350, with different holes. do you have a part number we can go off of?

Try 1105500. That's the GM number out of the CUCV parts manual.
 
thanks. i think he decided hes going to have the alternator rebuilt
 
I just asked for an alt from an early 80's cadi. They were 100amp and mathced the mounts perfectly. Cost less than $100.
 
bear76 said:
I just asked for an alt from an early 80's cadi. They were 100amp and mathced the mounts perfectly. Cost less than $100.

I went to Kragen and talked to the Guy and asked him to find me the biggest 12SI with Vbelt pulley he could find and he found me a 135amp from a special edition EFI caddy in the early 80's.
Cost me $125 but was worth every penny at 135AMP :D
 
muddybuddy said:
we are converting protechk5's m1008 to 12volt, what are you guys using?
I:dunno: but why convert the whole system when 24v gets you colder wires and starter,don´t need as much amps.
Just convert the GPs.
My M1008 is that way and work fine starts way easier than a 12v truck in the cold and haven´t eaten any starters (yet):dunno:
And if I would get a winch it would last longer I guess:wink1:
The only downside with the 24v system is it´s taking space from an OBA but I already got a 24v OBA:p:
 
Ronnie4wd said:
I:dunno: but why convert the whole system when 24v gets you colder wires and starter,don´t need as much amps.
Just convert the GPs.
My M1008 is that way and work fine starts way easier than a 12v truck in the cold and haven´t eaten any starters (yet):dunno:
And if I would get a winch it would last longer I guess:wink1:
The only downside with the 24v system is it´s taking space from an OBA but I already got a 24v OBA:p:

You are right about the benefits of 24v vs 12v, but here some of us end up with one battery and can still start our truck, can't do that with a 24v :D
 
Sorry about the hijack:o
I can see why but I think people should think it over properly before they do it BC of the benefits of 24v.
And If they convert their starters to 12v send the 24v starters to me:wink1:
I use two yellowtop optimas and they only take the space where one military battery was.
 
Ronnie4wd said:
And I can start my truck with one battery and without a starter:laugh:

You are cheatin, you have a manual tranny. :D
That's what I had on my perkins equiped K5 and I lost my alt and battery and I ran it with nothing just push start and go, mechanical injection no power needed.
:D
 
imiceman44 said:
You are right about the benefits of 24v vs 12v, but here some of us end up with one battery and can still start our truck, can't do that with a 24v :D

You really need a very strong battery to start a 6.2l with just one battery on a regular basis. :wink1:

Walter
 
dieselponyexpress said:
You really need a very strong battery to start a 6.2l with just one battery on a regular basis.
Actually all you need is a 1000 CCA rated battery with 2 ga or better battery cables. Works good down to 0 deg F (but you only get 1 or 2 tries at 0 deg F so your glow plugs better work).
 
dieselponyexpress said:
You really need a very strong battery to start a 6.2l with just one battery on a regular basis. :wink1:

Walter

I didn't say regular basis, but in a bind if one battery dies, you unhook it to not kill the other, and you can still start it, especially if it's already warmed up, just saying for limping home situations, can't do dat in a 24v :D
 
imiceman44 said:
I didn't say regular basis, but in a bind if one battery dies, you unhook it to not kill the other, and you can still start it, especially if it's already warmed up, just saying for limping home situations, can't do dat in a 24v :D
Another down side is having 2 alternators on the GM trucks... I have one not charging very well right now so the low battery drains the strong battery when parked. Then I find myself trying to jump a 24V truck with 12V :doah:
 
Hey, I'm well aware of the pros of a 12v system! :wink1:

But why not use the best of both worlds?

For example, a 24v winch is a nice thing imho.

The 2 generators are identical, just a different wiring/insulation. If one fails you can use the other just in case (some electric skills needed).

Jump starting in an emergency situation could be done from 12v to 24v.


kennyw said:
Another down side is having 2 alternators on the GM trucks... I have one not charging very well right now so the low battery drains the strong battery when parked. Then I find myself trying to jump a 24V truck with 12V :doah:
If your alt doesn't charge well, you do have a problem in either system. :doah:


Walter
 

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