[jscheublein]

I am finishing my 1964 Pontiac 2+2 Convertible with factory air. What is the correct alternator gm number for the car?

Thanks Jim

[BOB VIDAN]

My 64 MPC shows 1100633, all except TI, less pulley.

[johnta1]

I show 1100681 as the alternator?
(55 amp for Circ-L-Aire Conditioning)

['ol Pinion head]

believe I have a '64 usage '"681",
will ck alt stock for its date code & get back on here late tonight.

[BOB VIDAN]

633 is the service replacement number for 681.

[pfilean]

From 66 Parts

[johnta1]

Cool doc.



Any idea if the replacement alternator had the replacement # on it or the original #?

[pfilean]

I would really expect the service number to be stamped otherwise there would be no need for a new number.

[jscheublein]

I found 681 in the service manual. wrong one on car so will look for correct one. All other numbers match like they should - car only has 41000 miles

[tempest1964]

Nice Cat. Love those 8 lugs

[John V.]

If you understand how to use it, the Cross Reference Chart in the MPC will help you identify the OE p/n.

The Service p/n was for the bare alternator. It carried a specific p/n, you were expected to reuse your original pulley. A single Service p/n could therefore service multiple OE alternators.

The OE alternators were supplied by Delco WITH the pulley so they carried their own specific p/ns and were application specific but were not serviced that way..

The OE alternator p/n for your application is listed in a few places. The Shop Manual may be correct but there is a '64 SCN (Issue No. 2 IIRC) that lists the OE alt p/ns. It revised certain info in the Shop Manual, not sure the alt p/ns were affected.

Johnta1 might be able to help you out by posting a copy of the SCN page.

[389]

They use the 10 DN alt with the separate voltage regulator..

[johnta1]

Johnta1 might be able to help you out by posting a copy of the SCN page.

[Dick Boneske]

I have one for a '64 with air. The number is 1100681. PM if you want pictures or more info.