Alternator Pulley 1966 390HP, No A/C, No P/S

[Mike Z.]

OK guys, I am perplexed. My 66 390HP: I have had this car for some 28 years and just had not gotten around to restoring. I took the alternator that was on the car (correct #696) along with the pulley that was on it, and sent it out for restoration.

Car is all but finished and I am pre-judging before heading to the AZ Regional in May. In 6th addition of the TIMJG page 142, it shows the #696 alternator (w/K-66), then page 143 shows pulley number #3829193. My pulley has #3829387 AL stamped into the face.

I had on the shelf a repro 3829193, and it has the thick (5/8") back between the Vee and the fan surface, but the 3829387 on the car has a 3/16" thick back. In studying, page 142; it does not show the alternator if not equipped with K-66, but I have the correct one of K-66 anyway. Then on the pulley chart; has no A/C and w/A/C-mine would be no A/C 3829193, but does not differentiate K-66 like the alternator chart.

So, the last several days, I have been trying to track down an OEM 3829193 stamped pulley, as indicated in the TIMJG. I have talked to some folks that I believe are knowledgeable with alternators (they restore them) and have two opinions: one, they did not stamp the pulley (which I know is questionable because of the one on the car), and two; although, the P/N is 3829193, what is stamped on the pulley is 3829387 AL. I was told only the OEM units have the AL after the P/N.

So, can anyone shed any light on this question?: is the TIMJG lacking in clarity on this point? I have to commend the authors of this latest edition, as it is considerably more detailed than prior editions. And, secondly; what is the correct spec for the pulley I need for my application? Thanks, Mike

[Joe L.]

Re: Alternator Pulley 1966 390HP, No A/C, No P/S

OK guys, I am perplexed. My 66 390HP: I have had this car for some 28 years and just had not gotten around to restoring. I took the alternator that was on the car (correct #696) along with the pulley that was on it, and sent it out for restoration.

Car is all but finished and I am pre-judging before heading to the AZ Regional in May. In 6th addition of the TIMJG page 142, it shows the #696 alternator (w/K-66), then page 143 shows pulley number #3829193. My pulley has #3829387 AL stamped into the face.

I had on the shelf a repro 3829193, and it has the thick (5/8") back between the Vee and the fan surface, but the 3829387 on the car has a 3/16" thick back. In studying, page 142; it does not show the alternator if not equipped with K-66, but I have the correct one of K-66 anyway. Then on the pulley chart; has no A/C and w/A/C-mine would be no A/C 3829193, but does not differentiate K-66 like the alternator chart.

So, the last several days, I have been trying to track down an OEM 3829193 stamped pulley, as indicated in the TIMJG. I have talked to some folks that I believe are knowledgeable with alternators (they restore them) and have two opinions: one, they did not stamp the pulley (which I know is questionable because of the one on the car), and two; although, the P/N is 3829193, what is stamped on the pulley is 3829387 AL. I was told only the OEM units have the AL after the P/N.

So, can anyone shed any light on this question?: is the TIMJG lacking in clarity on this point? I have to commend the authors of this latest edition, as it is considerably more detailed than prior editions. And, secondly; what is the correct spec for the pulley I need for my application? Thanks, Mike

Mike------


Your application could not have used the GM #3829193. That pulley was used for applications with power steering. That's why it has the thick, spacer-like area between the pulley groove and fan. This spaces the pulley far enough forward for the alternator pulley groove to align with the power steering pump pulley. The 3829193 is 3-5/8" OD.

Applications with power steering and air conditioning used pulley GM #3883978. This is a pulley of similar configuration to the above but of smaller diameter 3-3/64" to provide for a higher alternator speed.

Your application originally used the GM #3829387 pulley which is exactly what you have on your car.

[Mike Z.]

Re: Alternator Pulley 1966 390HP, No A/C, No P/S

Joe, I have come to the same conclusion-guess the TIMJG needs a little tweeking, because that is not what it says currently. Thanks for the input.

[Ronald L.]

Re: Alternator Pulley 1966 390HP, No A/C, No P/S

Anyone make this 3829387 pulley?

[Paul O.]

Re: Alternator Pulley 1966 390HP, No A/C, No P/S

Hello Ron; I just came across this thread as I happen to be looking for correct pulley & fan for rebuild on my '66 427/425 with no a/c or p/s. based on the prior conversation sounds like I should be looking for that same 3829387 pulley.

Did you confirm that number was correct? Did you ever find anyplace making them?

thanks, Paul O.

[Michael M.]

Re: Alternator Pulley 1966 390HP, No A/C, No P/S

IMG_1586.jpgNot sure who makes the repro, but here is a picture of an original.

[Timothy B.]

Re: Alternator Pulley 1966 390HP, No A/C, No P/S

I have noticed that reproduction alternator pulley's don't have a key way cut into the ID like the factory parts.

[Paul O.]

Re: Alternator Pulley 1966 390HP, No A/C, No P/S

thanks for the image Michael... at least now I know what it looks like. do you happen to know what fan went with it?

I'm assuming this same pulley was used on the L72 engine.

[Michael M.]

Re: Alternator Pulley 1966 390HP, No A/C, No P/S

Paul,

I would have to check on the fan or Joe Lucia would know. Joe would also know what other applications this pulley is used for. I know this pulley is used for the 1966 L-79 small block and the 1967 Z/28.

[Joe L.]

Re: Alternator Pulley 1966 390HP, No A/C, No P/S

I have noticed that reproduction alternator pulley's don't have a key way cut into the ID like the factory parts.

Timothy------

Some of the original pulleys do not have the keyway, either. I just do not recall if there were 2 different part numbers or if they were all of the same part number but the drawing was revised at some point. In any event, the presence or absence of a keyway cannot be discerned with the pulley mounted on the alternator and no Corvette alternator ever required a pulley with a keyway.

[Joe L.]

Re: Alternator Pulley 1966 390HP, No A/C, No P/S

Paul,

I would have to check on the fan or Joe Lucia would know. Joe would also know what other applications this pulley is used for. I know this pulley is used for the 1966 L-79 small block and the 1967 Z/28.

Michael------

I'm in Italy right now and can't check my references but, as I recall, the fan used with this pully was the same one used for other 1966 Corvette applications except, obviously, those with an integral fan/pulley. Offhand, I do not recall the other applications for this pulley but there were at least several, Corvette and other GM.

[Ronald L.]

[Paul O.]

Re: Alternator Pulley 1966 390HP, No A/C, No P/S

Thanks guys for the additional input. Gives me better direction on what I'm looking for... now I just need to locate.