I'm putting an 89 350 in my 79 Chevy pickup. I bought the GM serpentine conversion, so now I have a reverse rotation water pump. I got a reverse rotation fan off an 89 Caprice, so I now have the correct fan.

The problem is that the fan off the Caprice looks to be too short, as in the distance from the water pump pulley to the radiator looks to be too long. When the old 400 was in the truck, it had a fixed blade fan with a short spacer on it, and it didn't cool very well, so I put a long spacer on it, which moved the fan closer to the radiator, and it did help cool it down quite a bit.

So the question is, can I put a stock 89 Caprice clutch fan on the end of a short spacer and attach it to the water pump? The fans are the same off a car or truck, so I can't just get a different fan. No thanks to the electric fans either.

Also, if anyone knows what size bolts I need to put this fan onto the water pump, I'd aprreciate it.

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So the question is, can I put a stock 89 Caprice clutch fan on the end of a short spacer and attach it to the water pump?

Also, if anyone knows what size bolts I need to put this fan onto the water pump, I'd aprreciate it.
Yes... You can.

The spacer isn't a problem at all when used in conjunction with a clutch.

BTW.... The fan blades should be 1/3-1/2 their depth out of the shroud.
Not all the way inside..... They pull more air out of the shroud if part of the fan is outside the shroud.
(If they ae all the way inside the shroud... they just beat air in a circular motion instead of pulling it out of the shroud to force more air in through the radiator.)

Different years/models often had different length "stems" built into the clutch unit. If a Caprice is the wrong length, do some looking around. Trucks, in particular, are often a good source for clutches with longer "stems" on them. Just make sure it's a serpentine/reverse rotation setup.

And don't forget about the 4.3L V6 engines- they use the same water pumps as a V8. And they DEFINITELY had longer stems on the clutch unit in many applications becuase they were 2 cylinders "shorter" than a V8 and often installed in the same engine bays as V8s.

When I did the serpentine belt on my car, I ended up using a '94 S-10 clutch on mine. The only way I figured out it would fit was that I was driving a '94 S-10 at the time.

I would put the spacer on it for now if you have to drive it and then take some measurements and find an auto parts store with a patient and understanding parts guy to let you go in the back with a tape measure.

B