7 Blade Fan Orientation

[Mark P.]

I am replacing a flex fan with a seven blade fan on m 67 small block AC car. The blades are stamped with 3931002 on one side and no number stamps on the opposite side of the fan blade. For proper air flow should the blades with the numbers face the engine or the radiator?

Thanks----Mark

[Wayne M.]

Re: 7 Blade Fan Orientation

Mark -- am not familiar with that later 7-blade fan you describe, but the '64-5 version "943" is installed as shown in pic.



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[Joe L.]

Re: 7 Blade Fan Orientation

I am replacing a flex fan with a seven blade fan on m 67 small block AC car. The blades are stamped with 3931002 on one side and no number stamps on the opposite side of the fan blade. For proper air flow should the blades with the numbers face the engine or the radiator?

Thanks----Mark

Mark------


The CONVEX side of the blades should face forward. Usually, the stampings are on the convex side of the blades.

As far as your application is concerned, the 3931002 is a SERVICE-only piece. However, it will perform just as well as the original and is generally similar in configuration.

[Larry M.]

Re: 7 Blade Fan Orientation

Mark:

Numbers on this fan should point to the engine.

This is a nice 7 blade fan......this fan was on my 1967 factory air car when I purchased the car in 1994. It works well.

Larry

[Jeff S.]

Re: 7 Blade Fan Orientation

Mark

As others have pointed out, 1002 is a very nice fan for use with OEM clutch and shroud, and was the service replacement part number for midyears and '68s with 327s and a/c. Be advised that the blades are made of a rather soft temper aluminum. Use some caution when storing or during installation, as they can mar or nick pretty easily.

Jeff

[David L.]

Re: 7 Blade Fan Orientation

The 3931002 7-blade fan (made by the Schwitzer company) was original equipment on 1968 Chevrolet models (EXCEPT the Corvette) with A.C. It was a "one year wonder" and service replacement for the Corvette and other earlier Chevrolets w/AC. The 3931002 fan is date coded and has the Schwitzer part number 913894 stamped on it.

Dave

[Mark P.]

Re: 7 Blade Fan Orientation

Thank You for your responses.

I do have another question related to one of the stampings. Each of the blades are stamped with 3931002 and the Schwitzer part number of 913894 with a build date of K67. One of the blades is stamped on the opposite side (side facing radiator) with the numbers L67 FG.

Any idea as so what this stamping represents?

Thanks-----Mark

[Joe L.]

Re: 7 Blade Fan Orientation

Thank You for your responses.

I do have another question related to one of the stampings. Each of the blades are stamped with 3931002 and the Schwitzer part number of 913894 with a build date of K67. One of the blades is stamped on the opposite side (side facing radiator) with the numbers L67 FG.

Any idea as so what this stamping represents?

Thanks-----Mark

Mark-----


The "L67" represents the date of November, 1967 (or, December, 1967 if "I" was used). The "FG" is the broadcast code for the fan blade assembly. This is how the assembly plant workers quickly identified the right part to be installed on a particular car.

[David L.]

Re: 7 Blade Fan Orientation

Mark,

The "K67" signifies October 1967 when the individual blade was made. The "L67" signifies November 1967 (NOT December 1967) when the fan was actually completely assembled. Generally on STAMPED date codes the letter "I" was not used so M = December. I have had Schwitzer fans with date codes of "M69" which were installed on 1970 Chevrolet V8 models with AC and very "early" 1970 Z28's (GM # 3947772, Schwitzer # 914087).

Dave