Alternator pulley question - L79 without AC or PS

[Chris E.]

Ok, so I was looking over my car in final preparation for the Iowa Regionals tonight. I came across the section in the TIM/JG where it gives the part number of the alternator pulley. Here is what I have:

3829587-AI

The book says I should have 3909815-AJ because I have the L79 (350 horse) WITHOUT A/C and WITHOUT Power steering.

Is that true?

I think I just replated my original pulley, that's why I'm wondering.

Also, was this part number the same in '66 on the L79 without AC & PS?

[Joe L.]

Re: Alternator pulley question - L79 without AC or PS

Ok, so I was looking over my car in final preparation for the Iowa Regionals tonight. I came across the section in the TIM/JG where it gives the part number of the alternator pulley. Here is what I have:

3829587-AI

The book says I should have 3909815-AJ because I have the L79 (350 horse) WITHOUT A/C and WITHOUT Power steering.

Is that true?

I think I just replated my original pulley, that's why I'm wondering.

Also, was this part number the same in '66 on the L79 without AC & PS?

Chris------


If the book says that you should have a GM #3909815, then the book is wrong. The 3909815 is a pulley and fan assembly. It was used on 300 hp engines but not L-79.

Your application should use a GM #3871242. The same was also used for 1966 without C-60, N-40, or K-19.

[Wayne M.]

Re: Alternator pulley question - L79 without AC or PS

....... The 3909815 is a pulley and fan assembly. It was used on 300 hp engines but not L-79.....

Chris -- here's two alt. pulleys w integral fan. The one on the right is the 3909815_AJ (you can see the stamping) that your book refers to.

[Chris E.]

Re: Alternator pulley question - L79 without AC or PS

Ok, so the stamping I have is on the PULLEY, not on the fan......is that right?

[R N.]

Re: Alternator pulley question - L79 without AC or PS

Ok, so the stamping I have is on the PULLEY, not on the fan......is that right?

Hi Chris,

I believe that's correct, I also believe the pulley is a deep groove

[Joe L.]

Re: Alternator pulley question - L79 without AC or PS

Ok, so the stamping I have is on the PULLEY, not on the fan......is that right?

Chris------


In your case, the fan and the pulley are separate pieces. There is usually no part number, at all, stamped on the fan.

[R N.]

Re: Alternator pulley question - L79 without AC or PS

Like this one....

[Chris E.]

Re: Alternator pulley question - L79 without AC or PS

Like this one....

YES, that is the one that I have with the part number stamped on the PULLEY.

Is that correct?

[Joe L.]

Re: Alternator pulley question - L79 without AC or PS

YES, that is the one that I have with the part number stamped on the PULLEY.

Is that correct?

Chris------


Assuming that you have an L-79 WITHOUT C-60 and WITHOUT N-40, I believe that GM #3871242 was originally used for your application.

I would not completely rule out the possibility that the GM #3829387 was used, though. It's just not what I would expect.