PorKen

I'm keeping the engine driven fan on the '86 for a while, and Shane was nice enough to lend me a fan with a good clutch. I couldn't find a writeup for all this info, so here ya' go.

Bearings from Porsche, ~$40/~$30. Local bearing shop, $7/$16. Later fan clutches (81.5 -) spec an odd bearing with an extended hub. A 4mm spacer on one side let's you use the common bearing. I used a thick 9/16" washer.

I removed the air pump so I needed the short belt. Doing a search I found the lawnmower belt from NAPA, and I realized why some used the 20", and others the 21". If you have option M319 - higher fan speed, which usually comes with M570 - rear air, the fan pulley is smaller (86mm), so you need a 20" belt. My '86 came with a small pulley, but I swapped in a big one (106mm) from the '81.


bearings installed | 4mm spacer | late clutch + fan | early clutch
M319 86mm pulley | 106mm pulley
4L210 belt installed

NAPA belts:
86mm|3-3/8" pulley: 4L200
106mm|4-3/16" pulley: 4L210

Bearings:
Front/Clutch: 6202 (2RSC3) [928 106 445 02]
Rear/Pulley: 6301 (2RSC3) [928 106 441 05]

Spacer:
ID: 15mm (9/16")
OD: <= 30mm
Height: ~4mm

PorKen

The bearing numbers above are a standard size among the bearing makers. Mine are ORS, made in Turkey. (You can get even cheaper bearings, without double seals. For the '81, I didn't ask for seals, and the total cost was ~$13.)

You may need a puller to remove the pulley. After it is off, remove the small Woodruff key. You'll probably also need a puller to get the clutch shaft out. (Don't get impatient and use a hammer, you'll ruin the threads... ) After that, I used a big hammer and a screwdriver through one bearing to knock out the other. An inside bearing puller would be better, here.

Lube up the new bearings and the arm with anti-seize, then press in the bearings. I used a vice, and a thick washer, the same OD as the bearings. Slide the clutch through, tap in the Woodruff key, and install the pulley.

With the short belt, you put the belt on the pulleys, then mount the arm. It may be a little tough to get the bolts in, so watch that you don't strip the water pump holes.

Rufus Sanders

One very simple way to run that fan w/o the air pump is to run it off the power steering pump, by offsetting the fan mount 14 mm forward. I used 3 14 mm spacers, longer bolts and a new belt (forgot the new length but 41 or 42" comes to mind). Use the power steering pump to tension the thing and you're good to go. - Ruf

PorKen

That's a great idea for pre-85, there's plenty of room. I'd probably do that on the '81 if I still had the fan. (I'm using just the A/C fan with a 75°c rad-switch.)

'85-'86, the PS pulley is behind the air pump/fan pulley. Also, the accelerator linkage is attached to the fan arm.

Rufus Sanders

Oh yeah, right. I forgot about the cable on the 85 86's. Nevermind... But the idea of running a cooler switch for the AC fan is a great idea. I may have to make that mod on pure principle.- Ruf

sharkmeister85

I just went through this repair, replacing my fan bearings and adding the "air-pumpless" NAPA belt. Ken's info was invaluable. However, I was confused with his description of "big" and "small" pulley and ended up buying the wrong size belt. Not having both sized pulleys to compare, I guess I should have brought my pulley and fan in and compared them more carefully to the photo Ken supplied. Although my pulley looked "small" to me, I must have the "large" one, requiring the L4210 belt. For the record, the fan pulley I have measures 4" in diameter (and the corresponding pulley on the crank is about 4" in dia. as well). Ken, next time just put it on the table and measure it up, will ya!
Happy Independance Day!
Glenn

lorenolson888

I am going to remove that entire belt setup...

going with an X and electric fans

here is my experimental solution...

I wanted to keep the stock throttle position for 85-86...

I bought the fan console for $10 at the wrecking yard

I sawed off the bearing then I made a holder and chucked it into a verticle mill...

sharkmeister85

That's where I want to go. I'm just taking it one small step at a time. I need to make sure I can still get through emissions testing. First the pump, then the cat. If I can still pass (which I expect I will), then I can rip out the air pump and replace the fan with an electrical one. Like you, I want to keep the stock throttle control position. Please post pictures and info of your "experiment" as you progress.
Glenn

sharkmeister85

That was fast! I was thinking along the same lines. Thanks!
Glenn

PorKen

Glenn,

You should know that I don't measure anything. Why do you think I have to make so many prototypes?

Did you use the plain bearing w/spacer?

Mike Frye

Glenn,

You should have no problem getting through emissions with the crossovers and high flow cats if your car is otherwise tuned well. My air pump is there basically as a means of adjusting the fan belt right now .

I'm hoping to pull it out soon and replace with either electric fans or the shorter belt.

sharkmeister85

Well, there's the rub. I was planning on going "catless".
Glenn

lorenolson888

more pics

PorKen

I think the belt driven fan is superior for A/C performance, if you drive in the city most of the time.

I just wish there was a easier/faster way to remove the throttle and fan brackets. Anytime I do anything on the front of the engine, I have to remove the air tubes, upper fan shroud, throttle bracket, and fan!

Imo000

Turkish bearings?!?!?!?!
Porken, I know you like to be cheap, just like me, but how much more would have been to get Timken or SKF instead? I’ve used Romanian made bearings once and they didn’t last long at all.


Nice write up by the way!