Author Topic: Six Bladed Fans  (Read 141 times)

Offline Lexi

Six Bladed Fans
« on: March 14, 2019, 10:59:35 AM »
Discussions regarding the Cadillac 6 bladed fan come up from time to time in the Forum. So now that I got mine out for painting for my engine rebuild, I compared it to another alleged Caddy fan your information and also comments.

My '56 has a six bladed fan which I assume is factory original. There does not appear to be a listing for the fan in the 1956 (March) Master Parts List, probably because it was introduced August 15, 1956 as per Cadillac Serviceman Supplement No. 3. The fan was listed as Part No. 1464740, intended for cars equipped with AC. Use of the fan was restricted to customers who complained of overheating with their (only AC equipped) '56 cars. So it looks like this was a "secret warranty" deal as no costing was noted. The 1959 MPL also does not list this part number, but it does list a 6 bladed fan and provides 2 apparent part numbers (but both are different from the '56 number). 7 bladed fans are also listed for model year 1959.

I have an extra 6 bladed fan here and compared it to the one I removed from my car. Just wanted to decide which was best to media blast and paint before installation. I have never compared both fans but once out of the car I observed that both are different. See attached image.

On the left is the unit removed from my car, (which has factory AC). Note the flat rivets and the more narrow in width vanes, (3.5 inches). Fan bolt mounting holes are capsule in shape, and appear to have been drilled by the factory. Overall width is 17 inches.

The fan on the right is said to have come from a '58 Cadillac. Note the domed rivets and the wider vanes, (4 inches). The fan bolt mounting holes are circular. When both are lying on the ground the '58 fan sits a little higher. Overall width is greater at 17 3/4 inches. I imagine this fan would draw more air.

Both fit the 1956 fan pulley hub.

Is the fan that came from my car an original '56 fan? I ask as I found it odd to have those different shaped mounting bolt holes, as if it were meant to fit other makes and models? While very similar in appearance, could it be after market? What do fellow members have on their cars? The AC system on my car appears all original. Is the other fan really from a '58? I usually stick to original parts and a stock look, but I am thinking of installing this '58 fan to keep the engine cool. I also hope that there is no impact on cooling because the fan will be sitting marginally closer to the radiator. Any comments? Clay/Lexi

Offline Cattle Axe

Re: Six Bladed Fans
« Reply #1 on: March 14, 2019, 12:33:21 PM »
Will the bigger one fit in the shroud?
1961 Series 62 Convertible
1962 Coupe Deville

"I got my self a cadillac but I can't afford the gasoline" (AC/DC down payment blues)

Offline Lexi

Re: Six Bladed Fans
« Reply #2 on: March 14, 2019, 02:02:39 PM »
Good point, but there is no shroud in a '56. So my thinking is the greater diameter, wider fan blades and slightly closer mount to the rad should result in the fan moving more air. That would be a good thing. The only semblance of a fan shroud in '56 was a rubber strip which helped to seal the hood (when closed) to the upper rad support area. Think it was to direct the in flowing air through the rad rather than have some of it lost by going over top of the radiator. But no fan shroud. Clay/Lexi

Offline JAG56Cad

Re: Six Bladed Fans
« Reply #3 on: March 15, 2019, 08:12:18 AM »
Clay,

I also bought a 6 blade fan which in now on the car, if I recall it was listed for either a ’57 or ’58 and it looks like the one on the right side on your picture with 4” blades width and rounded rivets heads.

I’m not sure if the one on the left side may well be the one listed under the Serviceman for the special fixes with ’56 A/C since that part # is not listed on the later MPLs.  ???

The one I have come with the spacer which it was not needed in my case but yes the 6-blade fan seat much close to the radiator than the original 4-blade fan. Also, my radiator is mounted inside the rail and bolted from the engine side, so it was modified from the original position of bolting it from the front, much easier to get to it when needed.  ;)
Jose Gomez
CLC Member #23082

Offline Lexi

Re: Six Bladed Fans
« Reply #4 on: March 15, 2019, 08:26:51 AM »
Thanks Jose. I think the spacer was only used with a double grooved fan hub pulley, (non-AC cars), so the 2 belts would line up. The tripled grooved fan hub pulley did not need one because it is a larger, longer unit, so the 3 fan belt alignment was OK. That is my best guess. You are right, there does not seem to be any mention in the MPLs for the apparent "one off" six bladed fan for 1956. My car is basically a survivor that has more or less been maintained. So I am guessing the fan on the left is the original fan. Perhaps of interest to those with '56s as to what that part looked like. Clay/Lexi

Offline Jon S

Re: Six Bladed Fans
« Reply #5 on: March 15, 2019, 07:26:47 PM »
Lexi - Does this help?  A 1958 6 blade fan:

Offline JAG56Cad

Re: Six Bladed Fans
« Reply #6 on: March 15, 2019, 08:47:39 PM »
Lexi - Does this help?  A 1958 6 blade fan:

Jon,

 ??? I'm counting 5 blades unless the 6th is hidden.   ;)
Jose Gomez
CLC Member #23082

Offline Jon S

Re: Six Bladed Fans
« Reply #7 on: March 15, 2019, 09:51:10 PM »
My understanding is the 1958 used 5; not 6 blades on the AC models; 4 on the non- AC.
Jon

Offline JAG56Cad

Re: Six Bladed Fans
« Reply #8 on: March 16, 2019, 06:42:42 AM »
Jon,

Very interesting  :o even the PL lists the fan blade as 6 blades so…!  ???  ???
Jose Gomez
CLC Member #23082

Offline Lexi

Re: Six Bladed Fans
« Reply #9 on: March 16, 2019, 10:20:57 AM »
Jon, your pictures are very interesting. I believe you have said that your car has been in your family since new? Any records of the fan being changed or other work that would suggest such? I ask as the MPL for that era does not list a 5 bladed fan. That said, the MPL does not list my 6 bladed 1956 fan part number as noted in that Serviceman bulletin either. It looks like whoever made the fans in my posts also made your 5 bladed fan as their similar construction suggests. Perhaps there is an answer in the 1958 service bulletins. Clay/Lexi