1967 BB A/C fan, 5 blade or 7 blade?

[Domenic T.]

I have a 5 blade 18" fan on my 67 BB, flat rivet. I converted it to A/C back in 71. While looking and reading about the fan I see a 7 blade and a 5 blade. The 7 would seem to be right and I don't remember where I got the 5 blade fan. It's not the original that came with my vette as my fan was damaged.

Dom

[Michael F.]

Re: 1967 BB A/C fan, 5 blade or 7 blade?

It is 5, not near my car or I would look to be 100%, 7 blade was for ac cars if my memory serves me.

[Larry M.]

Re: 1967 BB A/C fan, 5 blade or 7 blade?

I believe it is 5, not near my car or I would look.

The AC fan was five blades for 1967 cars. The part number should be #3888366. A "W" is stamped into one of the blade arms . Each blade is 4" X 5-11/16" with an overall diameter of 17-1/2 inch. The same fan was used for AC and non-AC cars.

[Michael F.]

Re: 1967 BB A/C fan, 5 blade or 7 blade?

GM parts book shows 66-68 with cac= 7 blades, bb were all 5 blade.

[David L.]

Re: 1967 BB A/C fan, 5 blade or 7 blade?

66-67 327 w/AC: GM # 3789562 or GM # 3863137 (both 18", 5-blade).
66-67 427 w/AC or wo/AC: GM # 3888366 (17.5", 5-blade)

Dave

[Domenic T.]

Re: 1967 BB A/C fan, 5 blade or 7 blade?

Thanks guys,
I picked up a 5 blade, flat rivet, 18" fan with a H on one blade arm and FRONT on it. Most likely Came from the parts dept or swap meet years ago. I will check the pitch.

Dom

[Wayne M.]

Re: 1967 BB A/C fan, 5 blade or 7 blade?

Thanks guys,
I picked up a 5 blade, flat rivet, 18" fan with a H on one blade arm and FRONT on it. Most likely Came from the parts dept or swap meet years ago. I will check the pitch. ...

Here's a pitch comparison: a "3770529" small block is on the bottom and (IIRC) the BB fan you describe is on the top.



c

[David L.]

Re: 1967 BB A/C fan, 5 blade or 7 blade?

Thanks guys,
I picked up a 5 blade, flat rivet, 18" fan with a H on one blade arm and FRONT on it. Most likely Came from the parts dept or swap meet years ago. I will check the pitch.

Dom

Dom,

Does your fan have 4 or 5 rivets/blade? Refer to the thread listed below.

Dave

https://www.forums.ncrs.org/showthre...hlight=3789562

[Domenic T.]

Re: 1967 BB A/C fan, 5 blade or 7 blade?

Dave,
I am going to the shop and check it. That thread was very helpfull.

Dom

[Michael F.]

Re: 1967 BB A/C fan, 5 blade or 7 blade?

6-76revision GM parts book, pg 1-3... 66-68 corvette w/CAC (327) (2nd design)...........3931002......18" dia, 7 blades-4 bolt circle...not saying in production, but what say you about this????

[Domenic T.]

Re: 1967 BB A/C fan, 5 blade or 7 blade?

Dave,
I have 5 flat rivets and it looks like tue blade on your post that's on top.

Dom

[Domenic T.]

Re: 1967 BB A/C fan, 5 blade or 7 blade?

Well,
I read some other posts and I think I have a problem other than 5 or 7 blades.
will a 18" clear the shroud on a BB 1967? I don't have my fan clutch yet and have not installed the unit to the water pump.

DOM

[Joe L.]

Re: 1967 BB A/C fan, 5 blade or 7 blade?

6-76revision GM parts book, pg 1-3... 66-68 corvette w/CAC (327) (2nd design)...........3931002......18" dia, 7 blades-4 bolt circle...not saying in production, but what say you about this????

Michael------


As far as Corvettes go, the 3931002 was SERVICE-only. It replaced the GM #3789562, which was an original Corvette fan, in 1972. The 3931002 did not even exist during the 1966-67 model years so it could not possibly have been used for ANY original applications during that period. The 3931002 was used in PRODUCTION for some 1968+ non-Corvette applications.

[Peter L.]

Re: 1967 BB A/C fan, 5 blade or 7 blade?

The fan blade assembly used on 1964 & 1965 Corvettes w/C60 was a 7-blade 18" dia. fan blade assembly, GM p/n 3853943, & is called out in the 1964 & 1965 Corvette AIMs & is listed in the Oct 1, 1966 Chevrolet P&A Catalog (18 dia., 7 blades). The 1966 & 1967 Corvette AIMs call out p/ns 3789562 & 3863137 (OPT.) for the "327" ENGINE & are 5-blade 18" dia. fan blade assemblies. The Oct 1, 1966 P&A Catalog lists p/n 3789562 (18 dia., 5 blades). Pete

[Michael F.]

Re: 1967 BB A/C fan, 5 blade or 7 blade?

Joe, thanks very much. I was wondering why it was listed but not used.