Is this alternator bracket correct?

[Michael L.]

Guys,

I'm trying to install the alternator on my 69 350/350 and having some difficulty getting the bracket to line up correctly. As you can see from the attached pics, there is a small bend in the end of the bracket where it mounts to the waterpump. As a result, the bracket deviates toward the rear of the engine and doesn't line up with the mounting spot on the alternator. I can "persuade" it to attach it but I wasn't sure if this was correct. Any advice is appreciated.

Mike

[Edward J.]

Re: Is this alternator bracket correct?

Mike, have you tried putting the stud to water pump first, (I believe no lock washer to pump) then add the braces with a lock washer and nut?

[Michael L.]

Re: Is this alternator bracket correct?

No I have not. May AIM shows both alt brackets under the stud with a lock washer. Not sure changing that would have much of an impact. Its not a minor alignment issue. Its the bend in the end of the bracket that results in it deviating posteriorly.

Mike

[Gary B.]

Re: Is this alternator bracket correct?

It should look like this. This picture is an early 70, but it carrid over from 69 until the cast bracket was introduced.
Gary

[Michael L.]

Re: Is this alternator bracket correct?

Ok so it clearly looks like the bend in my bracket isn't correct. Yours has no or only very slight forward bend to it, while mine has a significant posterior bend to it. I'll have to see if I can correct it or order a new one.

[Gary B.]

Re: Is this alternator bracket correct?

They bend pretty easy. You should be able to straighten it real easy. Lay it on a flat plate, hit it with a hammer and it will flatten out.
Gary B

[Joe L.]

Re: Is this alternator bracket correct?

Mike------


The brace you picture appears generally correct, except for one very important feature. The correct brace has about a 15 degree bend at about 1-1/2" to 2" from the lower end. The brace in your photo has the bend but it's in the wrong direction.

[Michael L.]

Re: Is this alternator bracket correct?

Thanks Joe. I'll try and see if I can bend it back into the proper angle but if not I ordered a new one from a vendor. I also noticed from Gary's photo that the stud that is holding these brackets isn't painted. I painted mine because I figured it needed to be in place to hold the lower alt bracket when the engine was painted, but looking at Gary's photo I'm inclined to think that there may have originally been a standard bolt there that was removed and replaced at the factory with the stud. That sound likely to you?

[Terry M.]

Re: Is this alternator bracket correct?

Thanks Joe. I'll try and see if I can bend it back into the proper angle but if not I ordered a new one from a vendor. I also noticed from Gary's photo that the stud that is holding these brackets isn't painted. I painted mine because I figured it needed to be in place to hold the lower alt bracket when the engine was painted, but looking at Gary's photo I'm inclined to think that there may have originally been a standard bolt there that was removed and replaced at the factory with the stud. That sound likely to you?

Michael,
You can determine the answer for yourself. (I will teach you how to fish, rather than giving you fish.)

Look in your copy of the 1969 AIM (Assembly Instruction Manual) to see if that stud shows a part number. If it has a part number in the AIM it was installed in St Louis and thus would be unpainted. If no part number in the AIM, it was installed at the engine plant (Flint in this case). Then it may or may not be painted depending on if it was installed before or after the engine paint operation. In the latter case examination of several original 1969 small blocks built around the time of yours will be necessary. Engine assembly operations did change over time, so in some cases one is reduced to looking for and at other unmolested examples for data points.

[Michael L.]

Re: Is this alternator bracket correct?

Thanks for that info Terry. Very helpful. It does have a part number so it was installed in St. Louis and should be unpainted.

[David L.]

Re: Is this alternator bracket correct?

Mike,

According to the 1969 Corvette AIM the brace (not bracket) part # is 3881816. Enclosed are a few of photos of some of the braces in my collection.

Dave

[David L.]

Re: Is this alternator bracket correct?

The 3884640 brace is similar in shape to the 3881816 brace but a different length.

[Michael L.]

Re: Is this alternator bracket correct?

Interesting David. My AIM appears to show the bend at the end that Joe mentions but I don't see a perceptible bend in yours. It should be around the 12" area but it sure looks flat to me. Either way I def have to correct mine to get it to work.

[David L.]

Re: Is this alternator bracket correct?

Interesting David. My AIM appears to show the bend at the end that Joe mentions but I don't see a perceptible bend in yours. It should be around the 12" area but it sure looks flat to me. Either way I def have to correct mine to get it to work.

Mike,

Over the past 35+ years I have had several 3881816 braces as well as 3884640 braces. I will check to see if I still have any in garage.

Dave

[David L.]

Re: Is this alternator bracket correct?

Mike,

I have only one 3881816 brace left in my collection. The offset measures about 1/4" or so as best as I can measure. My 1966 Chevrolet parts catalog (Oct. 1965) describes the 3881816 brace as follows:
Length = 12 31/32"
Slot = 4 7/64"
Offset = 17/64"
The 17/64" offset (0.27") matches my brace.
The bend is approximately one inch from the end that has the hole.

Dave

:.