pp000830

So I replaced the belts on my 96 Carrera last night.
The alternator belt was in shreds. While I was at it I replaced all three belts.
The first belt in was the fan belt. The replacement belt is hard to get on as it just barely clears the fan pulley shaft when trying to install it and it is stretched out to position on the fan pulley as you tighten the pulley screws. I used the existing pulley shims in the same position as used with the old belt.
The 2nd belt on was the alternator belt, again it seemed short and is stretched out to final position as the pulley nut is tightened. I used the existing pulley shims in the same position as used with the old belt.
After the two above belts were mounted I ran the engine for a few seconds and checked the belts to verify that they seated fully and had reasonable tension on them.
The third belt on was the A/C compressor belt. To get the old one off I had to remove the fan shroud A/C hose tie-down bolt and all four hold-down cap screws for the compressor. After mounting the new belt I was able to reinstall three of the 4 cap screws & nuts holding the compressor in place. To get the last cap screw in I had to lever against the fan housing to tension the belt enough to allow the cap screw to drop all the way in position. I had a concern about dislocating the fan housing so I used minimum force and checked to make sure the fan blades were not coming in contact with the housing after the install. I made every effort to remove any belt debris from the engine compartment. I observed stands of the failed alternator belt fiber sucked behind the fan. I used a forceps to remove all the debris I could see. When remounting the compressor i used duct tape to stick the nuts to be installed with the cap screws to my fingers so they would not inadvertently fall down where it would be difficult to retrieve them.
At first when running the engine I could here some slight ringing where the fan would strike some minor debris fibers that were still inside the fan housing I could not see to remove.

EMBPilot

I had the pleasure of doing this like 4 times. It's best to nurse the belts into their seated position. I did this by cranking the engine w the dme out as I tightened up the hub assembly, in increments. After everything was together I was able to get consistent readings w the napa KR1 kricket to keep an eye on the tension, I was neurotic about this and did it repeatedly over about 1000 miles.

I feel like using the same number of shims you took off is risky. I did this my first time around, did not accurately check belt tension, and 8 months later my fan bearing failed.

nine9six

Coincidence maybe?

EMBPilot

Could def have been.

pp000830

Took you advice and ordered the belt tension gauge - really cheap insurance. My thought is having a broken belt is not the issue, it's the potential collateral damage to the fan blades from the belt shrapnel is well worth keeping after the belts.
Andy

EMBPilot

Correction, KR1. The KR2 is too high of a scale. ( I have both had to go out in the garage and check) my apologies for confusing the two.

pp000830

Thank you for the guidance EMPPIlot,

I Purchase the Gates Kricket belt Tensioning guage. When I tested the belts after running them a coup of days the tension measured at the very low end of the scale. The belts are not slipping or making any noise so I see it as a no-foul situation.
It seems to me that the gauge is a very imprecise measuring device that probably only has value in identifying a grossly over tightened belt.
Andy :-)

KNS

I use the Kricket gauge and also like to run my belts on the looser end of the scale. When using a voltmeter plugged into the cigarette lighter, it indicates normal charging so I know they're not too loose.

BobbyT

Andy,

The Krikit gauge is quite precise and accurate, as shown in this video:


It just takes a little practice to get consistent repeat readings.

pp000830

Bobby T - Thanks for the vid.

JasonAndreas

V-Belt Tension Tester Special Tool 9574 TSB

BobbyT

Only $84.75 for Porsche Special Tool 9574 here:

http://www.eagleday.com/specialtools.html

That may include the Vaseline...

JasonAndreas

, even cheaper than Sunset Imports!

pp000830

BobbyT Thank you for the TSB, The noted tool is the same as the Gates tool I purchased. I inadvertently did the break-in procedure and measured the tension as correct acording to the TSB you were so gracious to provide above and validation as to my outcome.
Many thanks,
Andy