Factory fan 1966 L79

[Jim S.]

Re: Factory fan 1966 L79

Jim,

Your 5-blade 18" dia. fan is GM # 3863137 made by the Schwitzer Company (Schwitzer part # 912239) and date coded March 1966. The other 5-blade 18" dia. fan used on 1966 & 1967 Corvettes w/AC was GM 3778562 made by the Hayes-Albion Company (stamped "H", "FRONT", and "W" on the back side) with 4 flat rivets/blade not to be confused with the 5-blade 18" dia. fan stamped "H" and "FRONT" with 5 domed rivets/blade used on 1958-1963 Chev. V8 w/AC, 1961 Chev. 348, and 1961-1963 Chev. 409 (GM # 3749576).

My original 1966 Corvette 5-blade 17 1/8" dia. fan (GM # 3770529) is stamped "H" (for Hayes-Albion) from on the front side and "W" on the back side on one of the arms.

Some Hayes-Albion fans are stamped "H" and "FRONT" and a 2-digit number (the middle 2 digits of the 6-digit Hayes-Albion part number).
The 1966-1967 Corvette w/427 came with a 5-blade Hayes-Albion fan with "H", "FRONT", and "66" stamped on the front (GM # 3888366).
The "66" is NOT the last 2 digits of the GM part number. The "66" is the middle 2 digits of the Hayes-Albion part number.

Another example: One of the four different 7-blade 18" dia. fans used on the 1969 Z28 (GM # 3956684) is stamped "H", "FRONT", and "94". The Hayes-Albion part number is 159432.

I have studied 1960's and 1970's Chev. fans for the last 20-25 years and had as many as 50 fans in my "collection". I have sold many of my fans in recent years.

David,

Thanks for that great explanation , and history lesson.

Because of the C 6 on the blades, I knew it had to be correct , but I also knew it didn't match everybody's expectations of what they thought should be there. See Gary Beaupre's response for one .


Jim

[Gary B.]

Factory fan 1966 L79

David,

Thanks for the great part history. So, based on the date code it sounds like Jim's fan is original, i.e., balance weights were used on such Schwitzer fans on the '66 assembly line?

I hope the next edition of the '66 TIM&JG includes some photos of such fans to help out those of us who are ill-informed. I've never seen a Schwitzer fan with balance weights on any of the many '66 Corvettes I've examined.

Gary

[David L.]

Re: Factory fan 1966 L79

David,

Thanks for the great part history. So, based on the date code it sounds like Jim's fan is original, i.e., balance weights were used on such Schwitzer fans on the '66 assembly line?

I hope the next edition of the '66 TIM&JG includes some photos of such fans to help out those of us who are ill-informed. I've never seen a Schwitzer fan with balance weights on any of the many '66 Corvettes I've examined.

Gary

Gary,

There is no question in my mind that Jim's "C6 912239 SC" Schwitzer fan is 100% original as long as the date matches up with his car. I have had 4 or 5 of these fans in the part 20-25 years with 1966 and 1967 date codes and some of them had a balance weight. The 1966 & 1967 Chevrolets w/AC also used these same fans.
If you refer to page 338 in Noland Adams 63-67 Corvette restoration book you will see a picture of one of these fans (1966 Corvette 327 w/C60). The arms on the Schwitzer fan are rectangular. The Hayes-Albion fans have a arrowhead shaped arm connecting the blades.

By the way, I just dug out my NOS 3770529 5-blade 17 1/8" fan (box dated July 1986) and the only stamping on it is the letter "H". There is NOT a "W" on the back side.

[Jim S.]

Re: Factory fan for 1966 C60 equipped sb Corvettes

Jim - Looks like an excellent example of the "optional" fan blade assembly for a C60 equipped 1966 sb Corvette as Dave has described. Also, check your 1966 NCRS TIM&JG and you should find the description of the 2 fan blade assemblies that were used on C60 equipped 1966 sb Corvettes and I think you will see that the example of the stamped information on the blades is in fact exactly what's on your fan blade assembly. In addition, check C60 section of the 1966 Corvette AIM and you will see the 2 fan blade assemblies listed for the sb Corvettes.

These fan blade assemblies were also used on C60 equipped 1967 sb Corvettes.

Pete

Pete

I still have the 3rd addition of the 66 JG and it does not describe the two fans. I am waiting for the latest addition , where we will see.

I just looked thru the C-60 section in the AIM and could not find it there either . Maybe I have the third eddition of that as well ?

JIm

[Terry M.]

Re: Factory fan 1966 L79

Dave, While I don't have a dog in this race I would bet an article on the subject of fans (You might have to limit it to a year or two for length) for [i]The Corvette Restorer Magazine/i] would be of interest to a lot of members.

[Gary B.]

Schwitzer Factory fan 1966 L79; what frequency?

David,

What's your guess as to the frequency of use of the Schwitzer fan in '66 Corvettes, i.e., what percent of '66 Corvettes had that fan type? I'm guessing much less than 10% or else I would have seen one before now.

Gary

[Wayne M.]

Re: Factory fan 1966 L79

....By the way, I just dug out my NOS 3770529 5-blade 17 1/8" fan (box dated July 1986) and the only stamping on it is the letter "H". There is NOT a "W" on the back side.

Same with an original '529' (was off a '64) that I have. Mushroom head rivets, just the 'H' on the front hub; no 'FRONT' stamping, or no 'W' on the backside spider.

[Gary B.]

Factory fan 1966 L79

Guys,

I've seen a number of these fans (used and NOS) sold on e-bay in the past five year that have the H stamping, but not the W stamping. Some have the FRONT stamping and some don't. There definitely is a hodge-podge of varieties of these fans out there.

Gary

[Wayne M.]

Re: Schwitzer Factory fan 1966 L79; what frequency?

David,

What's your guess as to the frequency of use of the Schwitzer fan in '66 Corvettes, i.e., what percent of '66 Corvettes had that fan type? I'm guessing much less than 10% or else I would have seen one before now.

Gary -- Looking at an August '66 issue of CAR LIFE, where they have a road test shot of engine bay of an automatic, air, smog car. Looks like the fan has the tips bent forward with the weird tip configuration, like we see in '64-5 C60 cars (7-blade, 18" dia., #3853943). Only 2 blades are visible, so can't do a count. Could take a pic and post, if that will help.

FWIW, the '66 P&A30 (1st issue, Oct '65) shows the '943' for '64-6 w/C60, (2nd design) [I think this 2nd design designation comes from the '63 C60 fan # 3789562 (5-blade, 18") being the first design].

Then, the '67 P&A30 (again Oct '66 first issue) shows, for C60 small blocks, '63-4 using the 1st design '562', AS WELL AS '66-67 (2nd design). So for service, they seem to be acknowledging that by the end of '66, there was a different C60 fan than at the start.

This may be only muddying the waters.

[Rick S.]

Re: Factory fan 1966 L79

David,
Thanks for stepping up and explaining your research of fans, I am sure you have opened the eyes of many knowledgeable people who were unaware of your observations.

Regards,
Rick

[Peter L.]

Re: Factory fan blade assembly for 1966 sb w/ C60

Jim - Please check UPC C60, SHEET C2, ITEM 6, p/n 3789562 BLADE ASM - FAN & p/n 3863137 OPT. of the 1966 Corvette Assembly Instructions. Pete

[John H.]

Re: Factory fan 1966 L79

Another example: One of the four different 7-blade 18" dia. fans used on the 1969 Z28 (GM # 3956684) is stamped "H", "FRONT", and "94". The Hayes-Albion part number is 159432.

Dave -

My all-original/unrestored '69 Z/28 has its original 7-blade fan, stamped 3947772 and "914087 L68" on each blade, with the squared-off spider (for which I've been offered obscene amounts of money); I've seen other originals with nothing stamped on the blades and the "arrowhead" spider, so there were obviously several suppliers for this fan too.

[Gary B.]

Factory fan 1966 L79

I'll second Rick's statement. Always fun to learn new stuff.

Gary

[David L.]

Re: Factory fan 1966 L79

Dave, While I don't have a dog in this race I would bet an article on the subject of fans (You might have to limit it to a year or two for length) for [i]The Corvette Restorer Magazine/i] would be of interest to a lot of members.

Terry,
I'll think about it.
Dave

[David L.]

Re: Schwitzer Factory fan 1966 L79; what frequency?

David,

What's your guess as to the frequency of use of the Schwitzer fan in '66 Corvettes, i.e., what percent of '66 Corvettes had that fan type? I'm guessing much less than 10% or else I would have seen one before now.

Gary

Gary,
I have no idea.
Dave