1965 A/C 7 Blade Fan Purchase

[Bryan M.]

Hello,
I picked this fan up at Carlisle. It appears to be of the right configuration.
A stamped H is the only markings I could find.
What do you think? Service replacement?
Thanks!

[David L.]

Re: 1965 A/C 7 Blade Fan Purchase

It appears to be from your picture.
Are the rivet heads "domed" or "flat"?
Are the steel blades 6 1/8" long?
Is the width of each steel blade 4" on the arc and 3 7/8" on the chord?
Is the pitch 2 1/4"?
I once owned a NOS 3853943 7-blade fan with "flat" rivet heads that was stamped "H" (for Hayes-Albion, the manufacturer) and "6" (or "9") on the front and "W" on the back side on one of the arms. There was also a "25" stamping on one of the blades (5/32" digits). I believe the various stampings varied with the time of manufacture. I sold the fan in Nov. 1993 to Pete.
I believe the factory installed 3853943 fans that were installed on the 1964 and 1965 assembly lines have "domed" rivet heads but I am not 100% sure. I do not know when the rivet head change took place on the 3853943 fan. The 3853943 fan was discontinued sometime between Jan. 1976 and Dec. 1981 as per Chevrolet Parts History and replaced with GM # 3931002 (18", 7-blade, alum. blades), a fan that was only installed on production 1968 Chevrolets w/AC (not Corvettes). The 3931002 fan was "one year wonder" (1968 model year only) but was also used as a replacement for several other fans in later years.

[Wayne M.]

Re: 1965 A/C 7 Blade Fan Purchase

Bryan -- check out this link for a previous thread on the #3853943. Also, if you do an advanced search using this number, there's a fair amount of discussion of this 2-year factory installed part.

https://www.forums.ncrs.org/showthre...53943&uid=2452

I notice that your rivet heads are flat, and there's what seems to be an additional rivet on one of the blades (balancing ?)

The pictures of my 7-blade, in one of the posts of the above link, are from a '64, and the 'H' is the only stamping; mushroom-head rivets. Bought at Bloomington in the early '80s; came with the original Schweitzer fan clutch.

5th edition of 1965 Judging guide says round head rivets for 1965 (except 396 are flat). For my money, you have a service fan (ie produced after the original mushroom head stock was gone and they started another inventory run with the then-current flat head rivets, which lasted, as David says, until the fan was finally discontinued around 1976. Must have been a popular retrofit (in the hope of countering overheat) for it to be available in service that long, when it was initially used in production on only 4400 '64 & '65 air conditioned Corvettes.

[Bryan M.]

Re: 1965 A/C 7 Blade Fan Purchase

It appears to be from your picture.
Are the rivet heads "domed" or "flat"?
Are the steel blades 6 1/8" long?
Is the width of each steel blade 4" on the arc and 3 7/8" on the chord?
Is the pitch 2 1/4"?
I once owned a NOS 3853943 7-blade fan with "flat" rivet heads that was stamped "H" (for Hayes-Albion, the manufacturer) and "6" (or "9") on the front and "W" on the back side on one of the arms. There was also a "25" stamping on one of the blades (5/32" digits). I believe the various stampings varied with the time of manufacture. I sold the fan in Nov. 1993 to Pete.
I believe the factory installed 3853943 fans that were installed on the 1964 and 1965 assembly lines have "domed" rivet heads but I am not 100% sure. I do not know when the rivet head change took place on the 3853943 fan. The 3853943 fan was discontinued sometime between Jan. 1976 and Dec. 1981 as per Chevrolet Parts History and replaced with GM # 3931002 (18", 7-blade, alum. blades), a fan that was only installed on production 1968 Chevrolets w/AC (not Corvettes). The 3931002 fan was "one year wonder" (1968 model year only) but was also used as a replacement for several other fans in later years.

David,
The rivets are flat. The blades are steel and the blades measure 6 1/8"L x 4" w with a 2 1/4" pitch. I'm not sure how to get the chord measurement. Okay, I see how to now. The chord measures 3 7/8" and the measurement around the arch is 4".
The only marking that I can find is the stamped "H".

Bryan -- check out this link for a previous thread on the #3853943. Also, if you do an advanced search using this number, there's a fair amount of discussion of this 2-year factory installed part.

https://www.forums.ncrs.org/showthre...53943&uid=2452

I notice that your rivet heads are flat, and there's what seems to be an additional rivet on one of the blades (balancing ?)

The pictures of my 7-blade, in one of the posts of the above link, are from a '64, and the 'H' is the only stamping; mushroom-head rivets. Bought at Bloomington in the early '80s; came with the original Schweitzer fan clutch.

5th edition of 1965 Judging guide says round head rivets for 1965 (except 396 are flat). For my money, you have a service fan (ie produced after the original mushroom head stock was gone and they started another inventory run with the then-current flat head rivets, which lasted, as David says, until the fan was finally discontinued around 1976. Must have been a popular retrofit (in the hope of countering overheat) for it to be available in service that long, when it was initially used in production on only 4400 '64 & '65 air conditioned Corvettes.

Wayne,
Yes, the additional rivet must be for balancing. I have a "772" fan that has a similar rivet on it.
The guy I bought it from said it came off of a big block. It also came with a big block clutch.

[Bryan M.]

Re: 1965 A/C 7 Blade Fan Purchase

Bryan -- check out this link for a previous thread on the #3853943. Also, if you do an advanced search using this number, there's a fair amount of discussion of this 2-year factory installed part.

https://www.forums.ncrs.org/showthre...53943&uid=2452

I notice that your rivet heads are flat, and there's what seems to be an additional rivet on one of the blades (balancing ?)

The pictures of my 7-blade, in one of the posts of the above link, are from a '64, and the 'H' is the only stamping; mushroom-head rivets. Bought at Bloomington in the early '80s; came with the original Schweitzer fan clutch.

5th edition of 1965 Judging guide says round head rivets for 1965 (except 396 are flat). For my money, you have a service fan (ie produced after the original mushroom head stock was gone and they started another inventory run with the then-current flat head rivets, which lasted, as David says, until the fan was finally discontinued around 1976. Must have been a popular retrofit (in the hope of countering overheat) for it to be available in service that long, when it was initially used in production on only 4400 '64 & '65 air conditioned Corvettes.

Wayne,
Why would a 396 require flat rivets and an a/c car use round rivets? Was that actually called out somewhere during the assembly process?

[David L.]

Re: 1965 A/C 7 Blade Fan Purchase

Bryan,

I believe that the 1965 Corvette 396 did not appear until mid-production and that is probably when the switch from "domed" headed rivets to "flat" headed rivets occured by the manufacturer, Hayes-Albion. There were probably enough 3853943 7-blade fans already made with "domed" headed rivets made for the entire 1965 Corvette w/AC production, but who really knows. It would be interesting to find what rivet style was used on the last month of production of the 1965 Corvettes w/AC. A survey of original "late" 65 Corvettes w/AC might answer this question if that is even possible.

The extra rivet on one of the blades is for balancing. I have had as many as 100 fans during the last 30 years and some had the extra rivet.

Your fan should measure 18" in diameter. For some reason some people find it difficult to measure these fans accurately. I can not understand why. It is quite easy. Simply take the measurement from the center of the 2 3/8" diameter hole and measure to the tip of any blade. It should be 9" even, in your case. Or, place the 1 3/16" mark (one half of 2 3/8") of your measring device on the circumference of this 2 3/8" hole and measure along the centerline of any blade to the tip, 9" even in your case. The zero end of the measuring device will then be at the center of the 2 3/8" diameter hole.

Dave

[Bryan M.]

Re: 1965 A/C 7 Blade Fan Purchase

Bryan,

I believe that the 1965 Corvette 396 did not appear until mid-production and that is probably when the switch from "domed" headed rivets to "flat" headed rivets occured by the manufacturer, Hayes-Albion. There were probably enough 3853943 7-blade fans already made with "domed" headed rivets made for the entire 1965 Corvette w/AC production, but who really knows. It would be interesting to find what rivet style was used on the last month of production of the 1965 Corvettes w/AC. A survey of original "late" 65 Corvettes w/AC might answer this question if that is even possible.

The extra rivet on one of the blades is for balancing. I have had as many as 100 fans during the last 30 years and some had the extra rivet.

Your fan should measure 18" in diameter. For some reason some people find it difficult to measure these fans accurately. I can not understand why. It is quite easy. Simply take the measurement from the center of the 2 3/8" diameter hole and measure to the tip of any blade. It should be 9" even, in your case. Or, place the 1 3/16" mark (one half of 2 3/8") of your measring device on the circumference of this 2 3/8" hole and measure along the centerline of any blade to the tip, 9" even in your case. The zero end of the measuring device will then be at the center of the 2 3/8" diameter hole.

Dave

David,
Thank you very much for the detailed info. This fan fits your description.
My a/c'd 65 is a June 65 car. So, it sounds to me that there is a possibility that the flat rivets could be correct for it. I have been searching for a 7 blade fan and I feel pretty lucky to have found the fan at Carlisle. It was sitting under a table waiting for me to notice it. I got a great deal on it even with the attached big block clutch. About half the price of what I have been quoted by other parts people for the fan alone.

[David L.]

Re: 1965 A/C 7 Blade Fan Purchase

What type of big block clutch came with the fan?
Schwitzer type (bar strip) or Eaton type (coil spring)
Are there any stampings on the face?
The Schwitzer clutches were dated on the rim of the hub starting about 1965.

[Bryan M.]

Re: 1965 A/C 7 Blade Fan Purchase

What type of big block clutch came with the fan?
Schwitzer type (bar strip) or Eaton type (coil spring)
Are there any stampings on the face?
The Schwitzer clutches were dated on the rim of the hub starting about 1965.

The clutch is a coil spring type. I believe it is a newer version.
Markings on the front: Made in USA and ink stamp 27112505

[Page C.]

Re: 1965 A/C 7 Blade Fan Purchase

Hi Bryan, David and Wayne,
These are a couple of pictures from an original unrestored 1965 convert. with factory car. It's a mid June of 1965 production. This car's fan has the flat style rivets.
Page Campbell

[Bryan M.]

Re: 1965 A/C 7 Blade Fan Purchase

Hi Bryan, David and Wayne,
These are a couple of pictures from an original unrestored 1965 convert. with factory car. It's a mid June of 1965 production. This car's fan has the flat style rivets.
Page Campbell

Thank you Page. My car has a K8 (early June) production date.

[Page C.]

Re: 1965 A/C 7 Blade Fan Purchase

The car I referenced in the photos is actually a late June car with a K28 trim code. Sorry for the error(mid June) in the early post. You can't edit them after 12 hours.
Regards,
Page Campbell

[David L.]

Re: 1965 A/C 7 Blade Fan Purchase

Page,

It's nice to see an original 7-blade fan from a late 65 Corvette w/AC that has "flat" head rivets.

Dave