Fabbing an alt support bracket

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Doppleganger

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Also…. Clocking the housing may make using the other boss more accessible for your other idea
That is a HECKUVA idea. I had read about guys in their 3rd-4th gen camaro/firebirds re-clocking them (to do this same upgrade), but they were using alts with mounts that were 180* apart so I never paid any attention to it.

Gotta wait til Wednesday when the stars align and we have decent weather again to try this out.

Thanks!

:hat:

And no idea on the tapped hole next to the t-stat. Seems to me I saw someone who had this setup actually plugged it. Gotta check it out to see if its a blind hole or what. There's several ports all over it I have no idea about.

AND - and.....I have that GMT400 plate as those were the original brackets I was going to use had the FI I got matched the pic on the box. lol
 
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Doppleganger

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Update:

Had some side issues with this setup. First off, pulled the alt that was just sitting in the bracket and set it on the bench (on a towel). Heard small pieces of something rattling around in the alt - shook it and 3 small pieces from the brushes came out. WTF? So pulled it apart and the tip of one brush was broken off and 2 small chunks from the side of the other brush was missing. When I pulled the brush assy out, both brushes were like dried bread - very brittle. No idea why but glad it happened now and not later. Its a new GM gold-pro reman. Everything is discontinued (including the alt) but found an NOS brush kit and a pair of just bare brushes on feebay. Going to replace them ASAP. In the meantime, I found another new GM gold-pro reman on feebay for almost 1/3 what I paid for this one 3 yrs ago - so got it as a Plan B.

So, while the one is apart, its easy to play with the orientation to see where I want it. Here is how it looks clocked 90*. The outer boss is now in a similar position as the original smaller alt for a support to go from the alt to the exhaust manifold. A little modding to the original bracket would work. Would still like to see that inside single ear supported somehow. I do like the plug on the inside bottom - would allow me to integrate that harness into the loom with the coolant temp sensor right next to it.

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Radiohead

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You run a lot of current through things? That brush thing is interesting.
 

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An 1/8” or so sheet metal bracket would be low profile, light, and easily fabbed Mr. @Doppleganger

Bolts to lower threaded hole in alternator bracket and captures the alternator mounting bolt.

Either flat stock with two carefully placed 90* bends, or welded on tabs instead of bends. Maybe angle iron or Chanel iron could work well too.

Mounting bolt for alternator could be standard bolt with nut OR a captured nut built into the back of the bracket. I considered threading the back of the bracket but you would have to use super heavy steel to get enough threads for that big bolt.

Outline in orange, bends in blue and holes in green.

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Doppleganger

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An 1/8” or so sheet metal bracket would be low profile, light, and easily fabbed Mr. @Doppleganger

Bolts to lower threaded hole in alternator bracket and captures the alternator mounting bolt.

Either flat stock with two carefully placed 90* bends, or welded on tabs instead of bends. Maybe angle iron or Chanel iron could work well too.

Mounting bolt for alternator could be standard bolt with nut OR a captured nut built into the back of the bracket. I considered threading the back of the bracket but you would have to use super heavy steel to get enough threads for that big bolt.

Outline in orange, bends in blue and holes in green.

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That mount (on the original car the brackets were from) was just a through hole with a nut on the back, so the one bar on the other side that goes to the exhaust manifold was apparently enough to hold it. However this alt weighs alot more than the original, so why I wanted to maybe support both sides.

Kind of think a rod from the back of this bolt/mount to the intake (post 7) would be more help than the one to the exhaust manifold. That single ear is what has cracked on the guys who swapped these out in cars and never used any support brackets. Dunno.
 

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Is there a serpentine belt setup that would move the alternator to the right side of the engine ?
I realize that the wire harness would need to be lengthened but then it is possible that the factory strut rods to the intake manifold and etc would still mount like a factory application.
 

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I didn't read everything so of this has been covered already sorry. I believe that manifold is plastic,I wouldn't want to brace anything to it directly. As you stated before about switching to a stud,that's not a bad Idea,stud,nut bracket,nut. As for the adjustment side I'd look at tapping the hole in the alternator,use a stud,double nuts 2 rod ends and an adjustable center link. Should have worded this better. A stud sticking out of the tapped alternator boss. Then use 2 rod ends and an adjuster sleeve as your adjuster bracket. There may even be a turn buckle at home depot to use as the adjuster bracket.
 
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Doppleganger

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Is there a serpentine belt setup that would move the alternator to the right side of the engine ?
I realize that the wire harness would need to be lengthened but then it is possible that the factory strut rods to the intake manifold and etc would still mount like a factory application.
I haven't made the harness yet but the AC is going there. The exhaust manifold used a long bolt with a spacer. Kind of leaning thataway in addition to making a support rod on the opposite side to a stud on the intake manifold. If there was 2 ears on the inside bracket, I wouldn't mess with it. But just one that has a history of cracking when not supported. Its always something. lol
 

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I didn't read everything so of this has been covered already sorry. I believe that manifold is plastic,I wouldn't want to brace anything to it directly. As you stated before about switching to a stud,that's not a bad Idea,stud,nut bracket,nut. As for the adjustment side I'd look at tapping the hole in the alternator,use a stud,double nuts 2 rod ends and an adjustable center link.
The intake is aluminum and the exhaust is all cast. The original setup only used a rod to the exhaust manifold - but was a smaller/lighter alt too.
 

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Don't know if yoi are done yet but a couple of posts back I suggested maybe you could us a turn buckle as a tensioner bracket. We'll today I found a pic of some one who did just that. So I thought I post a pic,in case it helps you or another member
 

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Doppleganger

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Forgot how far this thread went also. A bit of an update.......so I took the original bracket that went from the alt to the exhaust stud, and with some heat and a vise was able to shape it to work with the 140A. Only issue was it was about 1-1/2" too long. Cut it down, chamfered the ends (for weld penetration) and then used a dab of 3M panel adhesive to keep it orientated correctly til its welded.
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Then on the other side of the alt, where there was a single small tab, I took a small misc bracket from a V6 Camaro and heated, cut, shaped, chamfered, dab of panel adhesive...etc, and got it ready to weld also.

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The welds will be grinded smooth and powder coated when finished. Dont think its going anywhere.
 

CalSgt

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Forgot how far this thread went also. A bit of an update.......so I took the original bracket that went from the alt to the exhaust stud, and with some heat and a vise was able to shape it to work with the 140A. Only issue was it was about 1-1/2" too long. Cut it down, chamfered the ends (for weld penetration) and then used a dab of 3M panel adhesive to keep it orientated correctly til its welded.
You must be registered for see images attach

Then on the other side of the alt, where there was a single small tab, I took a small misc bracket from a V6 Camaro and heated, cut, shaped, chamfered, dab of panel adhesive...etc, and got it ready to weld also.

You must be registered for see images attach

The welds will be grinded smooth and powder coated when finished. Dont think its going anywhere.
Thanks for the follow up, I like seeing how things work out.

Looks solid to me
 

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