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Discussion Starter · #1 ·
Slowly trying to replace Bubba one part at a time.

I noticed that my alternator belt didn't seem to be in perfect alignment with the bottom engine pulley (is there a proper name for that?). So I began looking at the bracket and noticed a couple things: a weld where there should be none, and a disconnected wire.

I was hoping someone could label what these connections to the alternator are as my Haynes wiring diagram in the back doesn't show the alternator (that I can see). Connect the dots:
#1 Brown ?
#2 Red electric taped to a black with white strip
#3 Red large gauge wire
#4 Black large gauge wire, CONNECTED TO NOTHING
#5 Green, goes to block maybe water temp wire?



The bracket I'm looking at doesn't look like the one on the Ecklers page for my year of car. Is my bracket different than yours?



Some views of the welded bracket:





 

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Discussion Starter · #2 ·
I was hoping someone could label what these connections to the alternator are as my Haynes wiring diagram in the back doesn't show the alternator (that I can see). Connect the dots:
#1 Brown ?
#2 Red electric taped to a black with white strip
#3 Red large gauge wire
#4 Black large gauge wire, CONNECTED TO NOTHING
#5 Green, goes to block maybe water temp wire?


So I used a little common sense after I posted this and did a search. D_B came up with this definition:

#1 - The brown is the resistance wire
#2 - The small red is the 'sense' wire that the alternator uses to asses how hard it needs to work to keep up with the demands of the electrical system.
#3 - The large red is the main power wire.
#4 - black is ground.

But I'm still a little baffled by the bracket. I've peeked around the internet and couldn't find a match to mine. All of the vette parts sites have a lower bracket that looks much different than mine.

And yes, the green wire according to this PDF: http://toutatis.be/corvette/docs/wiring/Chevy%20Corvette%201971.pdf is the Engine Temperature Gauge wire coming from the block.
 

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Glad you got the wires figured out. :thumbsup:

The bracket is designed for engines with no accessory holes in the heads. I've seen them a lot on power steering pumps too.
 

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Discussion Starter · #4 ·
Glad you got the wires figured out. :thumbsup:

The bracket is designed for engines with no accessory holes in the heads. I've seen them a lot on power steering pumps too.
Yeah, don't know why I didn't think of doing a search first. :huh:

Where do I find this crazy bracket? I've searched Google quite a few time with different terms and I've yet to see a single picture of a bracket like mine. I've searched for something like "Chevy 350 lower exhaust manifold bracket" and can't find it.

Are we talking about these unused holes in the head:



If so, why on gods green earth would Bubba not have used them? Did he not have the right bracket because the original broke and so he used what was on the garbage floor?

When it came stock from the factory, are those the holes they would have used for this bracket: http://www.ecklers.com/corvette-alternator-bracket-lower-small-block-1964-1971.html
 

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Discussion Starter · #6 ·
Zip says it's for a 72-82 alternator, not a 71

Hmmm, even though my vette is a '71 this is the correct bracket? Granted I've had the car about a week and I bought it through a bank repo sale, so I have very little prior knowledge about what was done to it. Maybe the heads have been switched. I believe at this point that the engine is original to the car as it's stampled CJL and the build date is L13 (July 13, 1971) so it was a very late 1971 and maybe they converted over to a newer bracket?

I will say that it does look like a better match than the one I was looking at that was categorized as a match for 1971 models:

72-82 Alternator Mount Bracket (Iron)


vs. 64-65 w/AC & 66-71 327 & 350 Alternator Mount Bracket


Thanks Tim, I would have never thought to look at the '72 designed bracket.

Jeff
 

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Discussion Starter · #8 ·
So to close this thread, the best photo I could come up with on the manifold is this:



It's very hard to read the stamp code on it but my best guess is 3749965, which according to what I was able to find on Google, belonged to a this era
Year(s)____Casting #___CID______Applications
1958-63___3749965____283,327___B Y

The number on the passenger side was much easier to read and is 3747042 which means:
Year(s)___Casting #___CID___Applications
1958-67__3747042____283___B Y

Looking at the new ones I can buy for that era does show holes on the manifold exactly where mine are for the alternator. So apparently both manifolds are not original to this car.
 

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two piece alternator bracket

I put a new alternator in my 77 last week and noted the bracket was not quite right so I went to find a new one. Quite a task seeing hardly any motor setups seem to use the high left position.
In Ontario I found a 2 piece bracket at Performance Improvements Speed shops. I dug out the bill and all it gives me is their stock number ( SR42283 and 73). Both pieces were chromed and about $42 Cdn. (made in the States)

The block attachment fits nicely around the Hooker headers and fastens with the same bolts.
The second piece joins the alternator to this main bracket and allows you to slide the alt. fore and aft till you get the pulleys aligned properly.

Let me know if you want the Mfg name and I will call them Monday morning (or the package didn't go out with the garbage, I'll check.)

Trapper 77:cheers:
 

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Discussion Starter · #11 ·
Ground

I found the one box - the two pieces were both from Spectre Performance. Hope this helps.

Trapper 77
Those look like the ones. Well, I had taken off my exhaust manifold and two of the three studs broke. That didn't worry me as I had already bought a used one for $40 that has the correct front mount holes and the correct bracket to go with it.

So I'm going to give that a try, my only slight disappointment was that the new/used manifold has the A.I.R. holes in it that I need to plug.


One other question. In my original post, you can see in the picture that the ground wire is not connected. I was curious as to why someone would do this? Shouldn't that ground be connected to the alternator casing?
 

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One other question. In my original post, you can see in the picture that the ground wire is not connected. I was curious as to why someone would do this? Shouldn't that ground be connected to the alternator casing?

The alternator case is already grounded to the engine block, the wire is a harness ground, so it can be grounded to anything convenient. You can ground to the alternator case if you like, but any bolt on the frame or engine would work.
 

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Discussion Starter · #13 ·
The alternator case is already grounded to the engine block, the wire is a harness ground, so it can be grounded to anything convenient. You can ground to the alternator case if you like, but any bolt on the frame or engine would work.
So putting the ground wire back on the alternator is of no consequence as it wasn't connected at all before?

I just don't like seeing wires hanging out there not connected to anything like it was when I bought it! There's enough wires not connected to anything that I have to worry about. :laughing:

I'll have another post about the "mystery wires" in my engine bay, but I'm gonna guess they are all from the TCS/CEC system. I looked at my engine heads between the 6 and 8 cylinders and there's supposed to be a temperature sending switch there, but right now it's just a big ol' plug. I've tried reading up on the '71 CEC system and what I've been able to find has been little. It seems most wiring diagrams were carried over from the '70 to '71 and don't show the correct wiring for CEC.
 

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ground

The OE Delco Remey that was on the car had the large black grounded into the bottom fireawall side of the alternator. The replacement alternator from Tuff Stuff offered the same connection. So that's where it is.

IF THERE IS ANY PROBLEM WITH YOUR BRACKETS ON YOUR REPLACEMENT MANIFOLD , LET ME KNOW. i KEPT ALL MY OE STUFF.

T;)RAPPER 77
 

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I put a new alternator in my 77 last week and noted the bracket was not quite right so I went to find a new one. Quite a task seeing hardly any motor setups seem to use the high left position.
In Ontario I found a 2 piece bracket at Performance Improvements Speed shops. I dug out the bill and all it gives me is their stock number ( SR42283 and 73). Both pieces were chromed and about $42 Cdn. (made in the States)

The block attachment fits nicely around the Hooker headers and fastens with the same bolts.
The second piece joins the alternator to this main bracket and allows you to slide the alt. fore and aft till you get the pulleys aligned properly.

Let me know if you want the Mfg name and I will call them Monday morning (or the package didn't go out with the garbage, I'll check.)

Trapper 77:cheers:
The bracket from a 69 to 71 or so SB pickup should work also, my bracket broke and I took the one from one of my dad's truck motors, pretty sure it was an original. I just don't know which motor it was from, the 69 or the 71.
 
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