Lower Hose and Fan Collision

[simssj]

I’ve got an ’87 924S NA that I’m piecing back together. Over the past weekend I finally got everything buttoned up and the car moved under its own power for the first time in about a month. New belts; new seals; new starter; new water pump. But the most onerous task has been trying to sort out the cooling system.

One of the original problems was that the PO (or some knuckle-dragging mechanic) had, at some point, re-installed the radiator without the upper mounts. This allowed the radiator to tilt backwards, allowing the upper radiator hose to get sliced by the alternator pulley, and the lower radiator hose to get sliced by the cooling fan.

I got everything sorted out; manufactured some mounts; ordered new hoses and I’m almost done. The one remaining problem I’m having is that the left-side cooling fan, despite being mounted perfectly, still wants to nip at the lower radiator hose. I’ve tried almost everything I can think of but the hose just can’t seem to stay away from the fan. (For now I’ve unplugged the electrical connector to avert disaster, while I look for a cure.)

Not sure if I’ve got the right hose on there or not. The one I got from Pelican said it was for an 87-88 924S. This is the hose I ordered and installed: 944-106-237-06-M51. It’s connected to the radiator with just the minimum amount of hose, since I’m hoping to push it “back” far enough to stay clear of the fans. But obviously something’s not right.

I’ve pored over the technical forums and have seen some oblique references to similar problems, but nothing with a big flashing neon sign, “STEVE: Here’s the solution to your problem!!!!”

I’ve seen suggestions that a “twist” of the hose, on the water pump end, might help. BTDT; it didn’t. I’ve seen a suggestion to lop off some of the water-pump end of the hose. Haven’t done that yet. Saw a suggestion that trimming the back-side of the blades of the fan will avoid collisions with the hose. Haven’t done that either.

I’ve seen suggestions that others with similar problems “may have the wrong hose.” This one looks “close” to the one I have, but appears to have a longer section at the bottom where it connects to the radiator: 944-106-237-05-M101. (The catalog says it’s for an ’83 – ’85 944.)

Anyone have any advice for me, or is this just a “keep fiddling with it until something solves the problem” problem?

[John_AZ]

Nip the tip of each fan blade where it hits the lower hose about 5mm or 1/4 inch. Just the tip not the entire outer edge.

I had the same problem with Gates after market hoses.

I just replaced both lower hoses with OEM Porsche stock and no problem.

J_AZ

[simssj]

Thanks, John. That seemed the most obvious and straightforward solution. But there were a bazillion options, and the car is new to me, so I didn't know if there were any "tricks" that I am not (yet) aware of.

Yes, I got the "Gates" hose. Nevermore.

I think I've heard every trick in the book for my old 993; I'm still on the left side of the learning curve on this whole "water pumper" thing. :-)

Appreciate the quick response.

[John_AZ]

and the obvious, nip all the right fan blades equally

J_AZ

[simssj]

Naturally! ;-)

[AKCJ]

Yes, I had to cut down the fan blades. I also cut a bit off of the hose.

On a side note, I recently did my belts and when I put in the (new) radiator to coolant tank hose I failed to tuck it in under the headlight cross bar. So the fan cut a nice slice in the bottom of it. Another new one on order. . . .

[simssj]

When you cut off a bit of the hose, did you cut it off of the upper (water pump) end, or the lower end?

The hose that I got on there now seems like it would clear better if the bottom was maybe 1/2 to 3/4" longer. So, I'm assuming that if the top was that much shorter, all would be good?

I plan to yank the fans out and trim them on the bench this weekend. So, I'll keep y'all posted.

[AKCJ]

My memory is not that good but I'm pretty sure it was the large end of the hose which is the end that's on the water pump. I think I took off about 3/8".

This helped bring the center, "S" curve part of the hose away from the fan.

[Nigel Haslock]

I had the same problem. The fan wore a hole in the hose, while wearing down the tips of the blades.

My fix was to cut about a quarter inch off the WP end of the replacement hose. Just keep trimming until the long section sits vertically and so clears the fan.

[v2rocket_aka944]

When I had this problem on my car...I just made a Volvo fan fit