Crankshaft pulley L79 w/ a/c

[Danny H.]

Need some help, just got the GM 3744043 crank pulley based on the JG for my '64 327/365 w/ a/c, but it doesn't fit the 15/32" A/C belt from Quanta, too small. Do I have the right pulley?

Thanks,
Danny

[Ray K.]

Re: Crankshaft pulley L79 w/ a/c

Danny

I believe the correct pulley for your application is #3858533, it should be correct for the wider 15/32" belt with a deeper / wider groove.

Ray

[David L.]

Re: Crankshaft pulley L79 w/ a/c

Danny,

CORRECTED for 1964 Corvette, June 7, 2011, @ 8:37 PM.

According to my 1964 Chevrolet Parts Catalog (effective Oct. 1963) the 1964 Corvette used the following crankshaft pulleys:

GM # 3747479: 64 Corvette (exc. Sp. H/Per., F.I., C.A.C.). Note: GM # 3747479 was replaced with GM # 3744043 in Dec. 1971 as per Chevrolet Parts History

GM # 3751232: 64 Corvette w/P/S (exc. 409), this is an additional pulley if equipped with power steering

GM # 3766987: 64 Corvette w/Sp. H/Per., F.I. NOTE: GM # 3766987 was replaced with GM # 3858533 as of 8/4/64 as per 1965 AIM (UPC L76, sheet 2) and as of August 1964 as per Chevrolet Parts History.

GM # 3850838: 64 Corvette (exc. Sp. H/Per., F.I.)

Do you also have power steering?

Dave

[Danny H.]

Re: Crankshaft pulley L79 w/ a/c

Danny,

According to my 1965 Chevrolet Parts Catalog (effective May 1965) the 1965 Corvette used the following crankshaft pulleys:

GM # 3747479: 65 Corvette (exc. Sp. H/Per., F.I., C.A.C.). Note: GM # 3747479 was replaced with GM # 3744043 in Dec. 1971 as per Chevrolet Parts History

GM # 3751232: 65 Corvette w/P/S (exc. 409), this is an additional pulley if equipped with power steering

GM # 3858533: 65 Corvette w/Sp. H/Per., F.I. (exc. 396)

GM # 3827843: 65 Corvette Sp. H/Per. Air Cond. w/P.S.

GM # 3850838: 65 Corvette (exc. Sp. H/Per., F.I.)

GM # 3863108: 65 Corvette (396)

Do you also have power steering?

Dave

Thanks for the info, I don't have p/s, just A/C, so the 3858533 is the right one?

-Danny

[David L.]

Re: Crankshaft pulley L79 w/ a/c

Danny,

I originally posted the C/S pulleys for 1965 Corvettes. I CORRECTED my post (06/07/2011 @ 8:37 PM) to show the C/S pulleys for 1964 Corvettes.

I believe that the correct pulley for your 1964 Corvette 327 w/SHP & AC is GM # 3766987. I once owned a 3766987 pulley many years ago and it is dimensionally the same as the 3858533 pulley but looks different.

I have a NOS 3744043 pulley (pictured on left) as well as a used original 3858533 (deep groove) pulley (pictured on right). Both pulleys measure about 6 3/4" O.D. but the 3744043 pulley measures about 1 1/4" wide while the 3858533 pulley measures about 1 1/2" wide so the spacing of the "V" grooves is obviously different.

Dave

[Danny H.]

Re: Crankshaft pulley L79 w/ a/c

Danny,

I originally posted the C/S pulleys for 1965 Corvettes. I CORRECTED my post (06/07/2011 @ 8:37 PM) to show the C/S pulleys for 1964 Corvettes.

I believe that the correct pulley for your 1964 Corvette 327 w/SHP & AC is GM # 3766987. I once owned a 3766987 pulley many years ago and it is dimensionally the same as the 3858533 pulley but looks different.

I have a NOS 3744043 pulley (pictured on left) as well as a used original 3858533 (deep groove) pulley (pictured on right). Both pulleys measure about 6 3/4" O.D. but the 3744043 pulley measures about 1 1/4" wide while the 3858533 pulley measures about 1 1/2" wide so the spacing of the "V" grooves is obviously different.

Dave

Thanks Dave, obviously I got the wrong pulley and someone needs to update that 63/64 JG too...

[David L.]

Re: Crankshaft pulley L79 w/ a/c

Danny,

I do not own any judging guides. I rely on my library of vintage Chevrolet parts catalogs, Chevrolet & GM parts history manuals, assembly manuals, and 30 years of research.

Isn't your car an L76 (365 HP, 327 engine) instead of a L79. The 1964 AIM does not list the L79.

I assume that you do not have an idler pulley (GM 3829191) since you have A.C. and the alternator is located on the driver's side. I also assume that your W/P pulley is GM # 3850979 and your alternator pulley is 3848023 as shown in the 1964 AIM. There is no water pump pulley listed in my 1964 parts catalog (Oct. 63) for the 64 Corvette (C.A.C. w/Sp. H/Per.) but my 1965 parts catalogs (Oct. 64, Jan. 65, and May 65) lists GM # 3848904 as the water pump pulley for 64-65 Corvettes (C.A.C. w/Sp. H/Per.).

You will probably have a very difficult time finding an original 3766987 C/S pulley but the 3858533 C/S pulleys are quite common.

Dave