yorkee

since I am taking the alternator out, this is the “while i am there” thing I want to do. Thought I can do a write up…

If you have older 944 (944/1) like me, very likely you have 3 blade fan. The general idea is that the 6 blade fan is quieter, provide more airflow, and help cooling better. It is more of a direct swap. That said, there are some small issue, the one I ran into is the old plug is “L” shape while the new plug is straight although adapter is correct, there are some clearance issue with the blade, as well as the fan mount. Here is my approach:

1. take out the fan. There are 6 bolt if they haven't fall off. the top 3 is behind the water hose that you can squeeze it flat and pull it out. (sorry no pic)

2. the old (top) vs new (bottom)


3. I use the the old fan mount with the new fan… so basically its emulate the mount rubbing against the rubber hose from water pump some experienced
if I use the old mount, the holder won’t rub, but there is some problem with the blade clearance.

4. I basically just grind down the edge of the fan blade to the old blade shape. Before:



After:



5. To make the clearance safer, I also stack the washer I took out from the old fan behind the bolt of the new fan




6. for the L shape connector, if I just use it as is, it will stick out touching the water pump engine / bell cover.



7. What I do is I reverse the cover, so it won’t stick out.


8. put everything back together, check the clearance of the fan, don't forget the 6 screws mounts and the electric plugs.


9. zip-tie all the wires, and the rubber hose at the top, run the car until water boil and see if it works! (or just turn on the ac)

tempest411

Why not keep the late assembly as is and just change the hose?

snb13

Mine was plug n play. Zip tied the cable to shroud and forgot about it.

NCporsche

For many years the three-bladed fan must have been sufficient for cooling the fist gen. 944s

I had to replace the lower radiator Hose and decided to replace the mounting blocks.

This is the condition of the radiator when I pulled it.

How this stuff accumulated in the inner radiator, I don't know but a good cleaning with air and water and the car is running much cooler.

944Time

>The general idea is that the 6 blade fan is quieter, provide more airflow, and help cooling better

How do you know this? Did you wind-tunnel test them?
Generally, more blades = less efficient.

tempest411

That's why these will never work!

MistaX

The 3 blade fans move no air in comparison to the 6. Extremely obvious difference in CFM.

They are significantly quieter, vibrate less, and by virtue of moving a ton more air, make the car run cooler.

Tiger03447

IMHO, more blades equals more chunks of air....I picked up a late model fan assembly from V2Rocket that he had laying around...Hopefully it will go onto my new(to me) radiator and fit up OK..The plug also looks like a similar plug to an early GM alternator plug..if anyone needs one...used on the 7127 series alternator. I'll check that out for a fit to be certain.

Noahs944

Thank you yorkee for taking the time to photograph & document the conversion.

KevinGross

Cool article, thanks, Yorkee.

NCPorsche, stop running over the neighborhood chickens!

yorkee

Thanks, it's not a big task but I hope this will help some.

My car don't have any problem with cooling, even with the old 3 blade fan. That said, my 3 blade fan is loud, to the point where my blood pressure raise a bit when I hear it turn on. I start playing a game where I will try my best to keep the car rolling in traffic without making the fan turn on. It will be less irritated if it's quieter.

It is easier not to drain the coolant.

That's good for you! mine will be grinding the water hose if I keep it as is.