GTA6T7

I replaced my engine cooling fan as part of preventive maintenance. The old fan had some cracks at the base of the blades that made me nervous. I purchased a new fan. It's a genuine Porsche part. I installed the new fan today and I can hear a very slight "tink" sound when I plip the throttle. I used the old belts and the same number of spacer shims when replacing the fan. I put a feeler between the fan and the housing and the fan blades are closer to the housing at the bottom than the top. It did not appear the fan touched the housing when the car is not running. Is there any way to adjust the fan so it is better centered? Any though are welcome. Thanks.

pp000830

First, check your belt tensions using a belt tensioning gauge. Too much tension is not only bad for the fan & alternator bearings but can cause fan blade clearance issues.
Dayco Belt Tensioning tool

Railmaster.

Too thick paint on the fan? I have read about the same problem when people have had their fans resprayed!

Railmaster.

Too thick paint on the fan? I have read about the same problem when people have had their fans resprayed!

pp000830

Seems this would be a self-correcting problem after a few hundred Revolutions of the fan?

GTA6T7

The belts may be too tight. I would not have though this to be possible because I used the same shims and belts. Given that the fan is being pulled down, it would make sense that the belts are pulling the fan down. Now I need to figure out how the shims work. As I understand it, I need more shims as more shims somehow loosen the belts.

gavonder

Correct. As you add shims, it spreads the pulley halves allowing the belt to sit lower.

P-daddy

Tighten the 4 nuts at the back of the alternator. These not only secure the black plastic cone in the back, they make sure the alternator is secured squarely to the fan shroud. Your blades rub the fan shroud because every time you blip, you’re pulling the alt/fan down thus making contact.

Greg Bell

I would check the bearings on the alternator, if worn they will allow the fan to be pulled down by the belt to make contact with the housing. Had the same problem with the fan, cracked and split on the ends. A new fan and new alternator bearings fixed it.

pp000830

Hi GTA,
Two or three 0.5 MM shims 964-106-268-30
Should give you a good range of adjustment.
While you are at it buying

• a couple of extra: square AC compressor hold down nuts 964-126-311-00 and
• a set of inner pulley hold down screws, 6x30mm socket head cap screws 900-976-004-01;

Also an extra set of belts:

• 999-192-343-50, 9.5 X 760 (outer alternator).,
• 999-192-338-50, 9.5 X 776, (inner fan)
• 999-192-363-50. 13 X 1085 (AC Compressor)

are good things to keep in your frunk .
Andy

GTA6T7

Great advice. I'll take it all back apart and try again tomorrow.

P-daddy

Yup. Make sure all 4 nuts are snug.

frankv

there should be torque settings for those alternator nuts, as well on the band that holds the fan housing in place. it is easy to overtighten these and then things can get out of whack,

- Frank

911PERVY

As Frank says, the band is probably too tight, slacken it off a tad and see

SpeedyC2

Another less likely (but possible, as it happened to me) option is the fan shroud has cracked at the mounting points and has warped slightly out of round.