goodspeed928

I got my ott cross over on (nice) but the air pump is norzy
Any way to fix that sound?

Jim bailey - 928 International

If you can find a "Euro" idler pulley also used on some 1980 USA cars it replaces the now useless smog pump . Or convert to electric fan / fans and lose the smog pump belt and belt driven fan clutch equiped engine fan ....and create room for a supercharger drive belt .....Yea that is it ....

Lagavulin

Remove the belt if you're not using it.

GlenL

On the pre-S4 cars the air pump is the tensioner for the only belt on the fan.

I took mine apart, lubed it and removed the internal pump vanes. Still haven't put it to use. Some folks have replaced the bearings but that looked hard.

If you search the archives, or measure well, you can find a belt that goes around just the fan and crank.

Or get a longer belt for the power steering pump. Extra points for shimming the fan out a bit so the pullies line up. Double extra points for doing that without sawing the radiator or fan shroud.

goldknight

Go to a elec. fan and lose belt and Air pump. I did on my 85 and she runs much cooler. I set the fan to after run so when the car is turned off the fan stays on till the mottor cools down to 140ish. And nope never had a bat. problem this way.

Garth S

I was previously advised that a 21" belt will drive the fan only - no tensioner req'd: Check the measure, as I have not done this (yet).

figgen

I had the same problem after the removal ( for track purposes only of course) of the cats. With the cats gone the air pump has zero backpressure and essentially free wheels making a bunch of noise. Scared the heck out of me when I first heard it. Removal of the air pump freed up some precious engine room and eliminated the noise. I used a shorter belt from the local hardware store to run the viscous fan.

GRGGOODSPEED

21" o.d or i.d ?

Garth S

Belts are measured od. Likely best to run a tape around the pulleys: even better, cut an old belt to fit & measure ( or go for the Crazy Glue ).

heinrich

In a pinch, a number of gerbels holding hands REALLY tightly will do the trick

heinrich

So, not OD or ID, but GC ... Gerbel Count ...

Normy

When I was driving back from Michigan last fall...just before the mountains of North Carolina, in redneck-territory Tennessee... I stopped for gas. As I was pulling away, I noticed a squealing noise. I pulled back into the station and popped the hood: Bye bye air pump, and also au revoir to the belt...burned through by the spinning front pulley. You guessed it: no fan. Well, it was a cool night, and the temp needle didn't even move, despite no cooling fan whatsoever...a tribute to Porsche's huge radiator. Of course...I never dropped below 70 mph, all the way to my parents house...

Anyway, I used a belt from Pep Boys that was originally intended for a riding lawn mower to drive the engine fan sans air pump. Do a web search on Rennlist for this- can't remember the belt number off hand, but it is blue and it was 21 inches...

N!
'85 S2 5 Speed

GRGGOODSPEED

Thank you N!

Mark R.

On my 84, the original air pump seized up solid, and while I was waiting for my new one to arrive, I used a small belt that I found at Pep Boys. It was made by Dayco, but the brand was Drive Rite. The part number was L421, and it also said 48X210 on the sleeve. I think it was actually from a utility tractor, or something. Anyhow, it worked great, and snugged up just right as I tightened the fan bracket mounting bolts.

HTH, Mark
Black 84 S AT (Daily)
Silver 88 S4 MT (Fun)
Atlanta

bshaw

I ran a 4L220 belt on my '84 when I had the clutch fan and no air pump. Now I'm running electric fans.