'57 Generator Mounting bracket

[Garry E.]

Were there different sizes of mounting brackets (the "U" bracket) for '57 chevy passenger cars and '57 Corvettes...? I found a mounting bracket that is 6" in total length...... I understand that mounting brackets on '57 Corvettes were 6 9/16" in total length..... Does this mean that the bases on generators for passenger cars were different from those on corvettes...?

Can anyone provide any insight on this.....?

Garry Eastwood
#38705

[Joe L.]

Re: '57 Generator Mounting bracket

Were there different sizes of mounting brackets (the "U" bracket) for '57 chevy passenger cars and '57 Corvettes...? I found a mounting bracket that is 6" in total length...... I understand that mounting brackets on '57 Corvettes were 6 9/16" in total length..... Does this mean that the bases on generators for passenger cars were different from those on corvettes...?

Can anyone provide any insight on this.....?

Garry Eastwood
#38705

Gary------


The 1956-1957 Corvette generator mounting bracket, GM #3728514, was unique to those Corvette applications. It is 6-7/64" overall length, according to GM.

There were several different brackets used for 56-57 passenger cars depending upon generator size and/or other installed options.

[Adam S.]

Re: '57 Generator Mounting bracket

Hi Gary, I was told by a few c1 guys that the power steering gen. bracket of 57 chevy pass cars would work,I never tried it myself but it makes sence to me , but I was also told the pass power steering U bracket is hard to find too!!!! I went with repo & ground down the flipped edges of repo to match my old rusted with extra holes U bracket, looks correct.

[Garry E.]

Re: '57 Generator Mounting bracket

Joe....

I wonder if I might have the correct bracket, but the wrong generator...... do you have the specs on the distance between the two attachement "ears" on a correct '57 Corvette generator.....? The generator that I have measures 8 7/16" total length between the ears....

thanks

Garry

[Joe L.]

Re: '57 Generator Mounting bracket

Joe....

I wonder if I might have the correct bracket, but the wrong generator...... do you have the specs on the distance between the two attachement "ears" on a correct '57 Corvette generator.....? The generator that I have measures 8 7/16" total length between the ears....

thanks

Garry

Garry------


I do not have that dimension.

[Adam S.]

Re: '57 Generator Mounting bracket

Garry, my inside to inside end plate measurment is 6 & 3/4"

[Gary C.]

Re: '57 Generator Mounting bracket

GE,

Easy way to tell if it's a Corvette generator and mount bracket assembly. Bolt mount bracket to the generator and position it like it would be mounted on a Corvette exhaust manifold:
1) if you can slip a finger between the bracket and generator, it's a passenger car assembly
2) if your finger can't even start to go between the bracket and generator, it's a Corvette assembly

Have never taken the time to analyze and measure Corvette generator ear length vs power steering generator ear length, etc., but this basic finger test works.

According to the P&A:
1) Corvette generator 1102043 and power steering generator 1102041 end plate is part #1934131
2) Both mount brackets are 1 11/16" high

GC
....

[Garry E.]

Re: '57 Generator Mounting bracket

All....

thanks for your input....!

Garry

[Garry E.]

Re: '57 Generator Mounting bracket

I measured the inside distance between the two ears on my generator...... 6 3/4"..... just like Adam's....... I must have the incorrect mounting bracket......

Thanks.....

[John H.]

Re: '57 Generator Mounting bracket

Gary------


The 1956-1957 Corvette generator mounting bracket, GM #3728514, was unique to those Corvette applications. It is 6-7/64" overall length, according to GM.

Joe -

This is probably confused by the sketch in Noland's book on page 146 that shows the #3728514 bracket as being 6.6" long, outside-to-outside.

[Cecil L.]

Re: '57 Generator Mounting bracket

GE,

Easy way to tell if it's a Corvette generator and mount bracket assembly. Bolt mount bracket to the generator and position it like it would be mounted on a Corvette exhaust manifold:
1) if you can slip a finger between the bracket and generator, it's a passenger car assembly
2) if your finger can't even start to go between the bracket and generator, it's a Corvette assembly

Have never taken the time to analyze and measure Corvette generator ear length vs power steering generator ear length, etc., but this basic finger test works.

According to the P&A:
1) Corvette generator 1102043 and power steering generator 1102041 end plate is part #1934131
2) Both mount brackets are 1 11/16" high

GC
....

Gary,
The difference is in the end plates on 57-59 P/S generator 1102115 vs Corvette 1102043 generator.
The 115 PS gen end plate was 1938726 and stands approx 1/4 inch taller than the 1934131 end plate on the Corvette generator.
As you pointed out, the 56 PS generator 1102041 used the same end plates as the 043 Corvette generator and is practically identical.

[Dan P.]

Re: '57 Generator Mounting bracket

According to the parts book the Passenger Car 1956 p/s Generator 1102041 and the 57 Corvette Generator 1120043 take the same end plates and armature. So all the dimensions have to be the same . But the parts book shows the 56/57 Corvette 3728514 U bracket to be 1 11/16 high and 6 a 7/64 long . The 56 passenger car Generator shows 1 11/16 high and 6 5/8 long .If the armature and end plates are the same how can the O.L. be different . Could the parts book be wrong and Noland Adams be right. The measurement that Noland Adams shows for the distance from the end of the U bracket to the centerline of the mount hole is 1.26 the passenger car U bracket measures 1 inch . Did they move the Generator forward because of the water pump being spaced out by the Motor Mount . The parts book shows a Harmonic balancer spacer 3734984 and Corvette Central shows A Harmonic balancer spacer .Are these spacers used to space out the balancer so it will line up with the water pump.

[Joe L.]

Re: '57 Generator Mounting bracket

Are these spacers used to space out the balancer so it will line up with the water pump.

Dan------


Among possible other reasons, YES.

[David L.]

Re: '57 Generator Mounting bracket

My 1957 Chevrolet Parts Catalog (Mar. 1957) lists GM # 3728514 in Gr. 2.274 as the generator bracket for 1956-1957 Corvettes w/30 amp. Last week I bought 4 generator brackets at a swap meet in Thompson, CT. Pictured below are two of them. The bracket on the top measures 6.0" long (possibly GM # 3836756) while the bracket with the stamped number "0" measures 6.1" long (or 6 7/64") which might be (????) GM # 3728514 but maybe not. The 6.1" long bracket came with two 5/16"-24 X 1 1/4" bolts with the "E" marking, two 0.11" thick washers, and two 0.31" thick nuts with a "notch" stamping on each of the 6 sides of the hex.

Dave

[Richard M.]

Re: '57 Generator Mounting bracket

David, Great photos and reference info.

I've never seen nuts like that. I'd think they may be a form of lock nut, whereas a compound jaw press is used to squeeze the ID a few thousandths. Interesting.

Rich