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So I did the Pontiac alternator upgrade

dremu

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And my local parts guy even took my totally burnt old 10si flavour in as core, though at the $15 rate for it and not the $50 they get for the Pontiac core :whistle:

However, my existing bracket was nowhere near fitting, so I had to fab an upper bracket. (No big deal, this is why I own a welder!) I s'pose it could be 'cuz I put it on a big block -- maybe all y'all who've done this did it to an SBC?

Once it was mounted, the wiring was almost easy. I did have to chase the factory alternator-to-battery feed through about six feet of tape-wrapped harness, and clean that mess up :mad: However, that meant I could drop in a nice short section of 8AWG directly from the alternator to the battery (the batteries have a 4AWG jumper between them, direct, no isolator.)

I used a cut-off old-style extension and the new-style 4-pin plug to adapt my existing wiring to this alternator, so I can drop in the old one if this one blows up or whatever. I didn't have the brown wire troubles that some folks (Rootbreaker?) had; I just heatshrinked that one off and hooked the red and black wires up.

Pix:

http://www.slosh.com/dremu/big-alternator-1.JPG

http://www.slosh.com/dremu/big-alternator-2.JPG

http://www.slosh.com/dremu/big-alternator-bracket-boogers-1.JPG

http://www.slosh.com/dremu/big-alternator-bracket-boogers-2.JPG

http://www.slosh.com/dremu/big-alternator-bracket-boogers-3.JPG

The welds are better than they look in these pix, really :rolleyes: The bottom piece is a length of angle iron with one side trimmed off from some of it, custom bent to the bizarre angle of the original mount points. The other piece is an adjuster for a York from a Volvo (I *knew* I've been hoarding those for a reason!) and again, though it doesn't show in the pix, it's welded all the way up the angle iron, ~1", so it's bloody sturdy.

Anyway, I'm happy ... I get a steady 14.7V at idle, even with the highbeams on... good wiring is of course part of that, including the relay upgrade for the headlights, but I was amazed to see that the spec sheet for this particular unit (spec'd at 140A) says it put out 160A peak! :eek1: Can't imagine I'll be whanging it that hard, but it's nice to know my batteries will stay charged.

-- A
 
1979jimmy350 said:
whats the benfits of the pontaic alternator vs say a chevy one from a serp setup/

140A stock is the kicker. ('94 Pontiac Trans-Sport with rear AC, btw) Cheaper than a high-zoot aftermarket alternator, and off-the-shelf availability of replacements, etc.

'Cept for the capacity, I imagine it IS a Chevy one with a serp setup... it comes with a serp pulley; I switched pulleys with the other one to fit my V-belts ('74 BBC.)

If you have a 105A or so stocker, it may not be worth it ... but mine was a 63A or thereabouts, and between towing, charging both batteries, and the fact that the one in there is a bazillion years old ... I wanted something I could trust, and why not supersize it? :D

-- A
 
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I tried the upgrade a while back.. had nothing but problems...
I will re-visit it eventually...
I mounted my alt up.... used the cutoff plug and tapped into my wires.. truck wasnt charging... bought the $25 plug (with resister in it) 2 to 3 plug one... and that didnt work.. I eventually gave up and threw a second battery in my truck... I do want to get it working eventually..... but not on my priority list...:crazy:

so I will be re-visiting this later... a long time later...
 
RootBreaker said:
I tried the upgrade a while back.. had nothing but problems...
I will re-visit it eventually...
I mounted my alt up.... used the cutoff plug and tapped into my wires.. truck wasnt charging... bought the $25 plug (with resister in it) 2 to 3 plug one... and that didnt work.. I eventually gave up and threw a second battery in my truck... I do want to get it working eventually..... but not on my priority list...:crazy:

so I will be re-visiting this later... a long time later...

Hmm. Alternators want two things to make them charge, the exciter voltage, and enough RPM's.

It seems like you wired everything every which way ... but I'm curious, did you fiddle with the pulley? I donno if you're running serp or V-belt or what, but maybe the damn thing just isn't spinning fast enough?

You had yours tested, right, so we know it's good?

-- A
 
Cool up grade. Question: Does it say anywhere on alternators what the amps are on them or how do i find out?

Also, Dremu, that engine compartment need a little tidding up. Looks like you have a lot of wires on or real close to the manifolds.
 
Any way to get this to work on say a '94 chevy truck?? What about wiring it up??

I had never heard of this before
 
'94 Chev truck probably already has a CS130 or 144 on it.

AFAIK, all Delco alternators are stamped with the amp rating on them, some rebuilds/aftermarket ones appear not to, or to grind off the GM numbers. Any original GM alternator I've seen has the numbers on the case.
 
'94 Chev truck probably already has a CS130 or 144 on it.

AFAIK, all Delco alternators are stamped with the amp rating on them, some rebuilds/aftermarket ones appear not to, or to grind off the GM numbers. Any original GM alternator I've seen has the numbers on the case.
I was just wonderin cause as i look at the voltmeter i notice it only says it's charging at 13 :dunno:

Where as my '83 is closer to 15
 
Also, Dremu, that engine compartment need a little tidding up. Looks like you have a lot of wires on or real close to the manifolds.

Since this thread is two years old, and I know he has swapped his motor; I think he had tidied up those wires loonngg time ago.
Another reason to run the Pontiac alternator is the mounting lugs are 180E. The later models chevy with the serpentine setup have the lugs at 120E.
I'm not really a fan of the CS alternators. I had rebuilt CS alternators go out after a few months.
Of course, that alternator looks like it came from a industrial application.
 
Any way to get this to work on say a '94 chevy truck?? What about wiring it up??

if you have the aluminum style serp belt brackets its easy for 124 amp option. or if you have a local starter/alt shop thay can build you one. in the 200 250 300 350 400 amp ranges. i am haveing one built at 225-250 and its 50 buck more than store 125 amp.

go get one for a 96-97-98 c/k truck with 350 and optional alt in the 124-125 amp range. its a cs144 housing with 2 lower ears and fits in place of the cs130 you have. just need to open up the tiny 10mm bolt hole a bit. and has the correct plug also.
 
if you have the aluminum style serp belt brackets its easy for 124 amp option. or if you have a local starter/alt shop thay can build you one. in the 200 250 300 350 400 amp ranges. i am haveing one built at 225-250 and its 50 buck more than store 125 amp.

go get one for a 96-97-98 c/k truck with 350 and optional alt in the 124-125 amp range. its a cs144 housing with 2 lower ears and fits in place of the cs130 you have. just need to open up the tiny 10mm bolt hole a bit. and has the correct plug also.
right on ;)

Also i didn't even realize this was 2 years old :doah:
 
Also, Dremu, that engine compartment need a little tidding up. Looks like you have a lot of wires on or real close to the manifolds.

LOL. Yeah, that was while I had everything undone to remove the original charge wire, which went from the alternator back to the firewall all wrapped up in a harness. I did tidy things up before I ran it. I take tons of pictures during my projects, especially in the middle when I'm taking breaks, so as to document details for future reference and CK5 posts :deal:

My wife thinks it's crazy that I have ~1000 pix of the crew cab and twice that many of the K5 ... but when somebody posts up and says "How does the Illudium Q-36 Space Modulator mount to the 14bff disc converted fizzbin?", I can not only describe the proper mounting, but show a picture as well, which with my photo skills is worth at least five hundred words anyway :D

And, as noted, the manifolds (and indeed most of that motor) are no longer in the truck :haha: Thank you all for remembering my trucks :bow:

-- A
 
Also for those with a 91ish suburban a Buick Roadmaster Alt bolts right up. 140 amp as well. Since it's not the 180deg one. Hope that helps someone. I took pics of mine when I installed as well but really really easy.
 
I was just wonderin cause as i look at the voltmeter i notice it only says it's charging at 13 :dunno:

Where as my '83 is closer to 15

You need to check the alternator output with a voltmeter. 15 IMO is too high, ESPECIALLY off the fuse panel, as that's probably 16V at the alternator, assuming the gauge isn't off a volt or two...but that's why you test alternator output with a voltmeter, to verify your gauge readings.

13V at the guage is about right with roughly .5-1V drop that I've found common on these trucks by the time the wiring reaches the gauge. But again, using a voltmeter, you will KNOW what the gauge is reading compared to alternator output, and what your voltage drop is to say, the fuse panel.
 
You need to check the alternator output with a voltmeter. 15 IMO is too high, ESPECIALLY off the fuse panel, as that's probably 16V at the alternator, assuming the gauge isn't off a volt or two...but that's why you test alternator output with a voltmeter, to verify your gauge readings.

13V at the guage is about right with roughly .5-1V drop that I've found common on these trucks by the time the wiring reaches the gauge. But again, using a voltmeter, you will KNOW what the gauge is reading compared to alternator output, and what your voltage drop is to say, the fuse panel.
yeah i seem to have misplaced mine so i'll have to make a trip to my dad's :doah:

Thanks
 
I ended up useing the old style big case A.C. DELCO out of a 70'S CoupeDeVILLE or Delta 88.100 amp's all day long and it's never really working too hard. They are only around $45 to $50 rebuilt.
 
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