Fan Clutch

[Thomas F.]

My 69 does not have a fan clutch. It only has a flex fan blade that turns all the time. Is this good or bad?

[Joe L.]

Re: Fan Clutch

My 69 does not have a fan clutch. It only has a flex fan blade that turns all the time. Is this good or bad?

Thomas-----

It might function OK if your car cools satisfactorily but it's "hokey" and definitely not original. In my opinion, these things are an "eyesore" in a Corvette engine compartment.

As far as I know, GM or any other auto manufacturer never used a flex fan on a PRODUCTION vehicle. It certainly would have been far less expensive for them to use a flex fan instead of a blade assembly with fan clutch. So, I figure they must have some good reason for not going the flex fan route.

[Richard G.]

Re: Fan Clutch

An additional reason not to use them is most have the blades in an even pattern around the hub.
Because of this, they tend to make a sound like a jet. Noisy at the very least.
This is the reason the factory fan blades have them blades attached in an none symmetrical pattern.
A huge difference in the noise levels between the two designs.
Rick

[Thomas F.]

Re: Fan Clutch

Thanks Joe and Richard for this information. Maybe I can find myself a fan clutch.

[Joe L.]

Re: Fan Clutch

Thanks Joe and Richard for this information. Maybe I can find myself a fan clutch.

Thomas---------


You'll also need a fan blade assembly if you're going to replace the flex fan. Original fan clutches and fan blade assemblies can be very pricey. Reproductions of both the clutch and fan blade assembly are available but they're a little pricey, too.

If you're not so much concerned about originality and are more concerned about cooling performance, I highly recommend using a GM #88961768 fan clutch, aka Delco 15-4950 and one of the 1971-81 Corvette fan blade assemblies, GM #3991427, GM #342715, or GM #469580. These are all GM-discontinued but you should be able to find them used. You have to use these fan blade assemblies with the clutch I mentioned because original 1970 and earlier fan clutches use a different bolt pattern for fan blade attachment. The fan clutch I mentioned has a dual bolt pattern for attachment to the waterpump flange so you can use it with a 1970 or earlier waterpump.