clib

My alternator belt broke so I figured I would replace all belts now. Using p-car DIY I have gotten down to the fan belt pulley. Using a good allen socket 1 of the 3 5mm allens came out. The other two wont and stripped easily. Using the suggestions here...................

http://p-car.com/diy/vbelt/belts.html

I tried with vice grips, penetrating oil, and last with a chisel to get an edge started, but am getting nowhere. My next thoughts are to chisel the head flush and remove the pulleys and then try a stud extractor on the remaining threads. Anyone have any better ideas that have worked for them?

Final question, when replacing those allens I want to use something with a more secure head but can only find bolts without shoulders (threads all the way to flange). Unsure if that will cause any problems.

thanks for any help

User 122821

You can grind a slot into the heads and then use a flathead bit in a socket wrench to remove them. The chisel will probably damage the alt bearings. The replace allens from the dealer seemed to be harder than the originals.

black ice

Vise grips will work. But you have to put them on REALLY TIGHT.

I've botched these before - they will not stip if you get the key fully seated.


dave

Garth S

The heads are quite ( obviously ) soft .... sharpen your small cold chisel, and start a cut radially - then tilt the chisel for a tangential blow - they will come out.

Alternatively, take the next larger size Torx bit, and drive it into the stripped 5mm hole: the hammer smack ( axis of the bolt) often loosens the threads, and is a good first step on many tricky bolts as a general practice: it should turn out.

All easy steps failing, grind the heads off as you suggested with a dremel ( chisiling off will be enough to potentially damage bearings). The stubs of the bolts will come off easily once the strain is released.

clib

Tried everything. I had fair warning about the potential for stripping these, even bought a new 5mm allen socket for the job, used penetrating oil, but the other 2 were not coming. Trying the vise grips wouldn't get sufficient purchas; grinding a slot for a screw driver just left me with the same soft metal that failed in the first place and it failed again. I finally grinded them off carefully. As garth noted above, once the tension from the pulley/shims was released they could be easily spun out by hand. The threads were not corroded at all.

THANKS FOR ALL THE SUGGESTIONS

Maybe it has to do with the heat cycles or maybe its intentional design to prevent over-tightening these things (but I'd think a torque wrench would be a better concept), and maybe its because mine have been on for so long (only 35K miles but 13 years). All the belts showed some significant cracks on the inner surfaces when I could get them off and inspect them.

MY ADVICE TO OTHERS; Change the belts at the 30K service - some shops and dealers say they inspect instead and leave if OK (my experience with 2 different shops). I don't think you can adequately inspect these nor rely on that inspection to predict lifespan. The fan belt will instantly strand you - no driving, the alternator belt might give you 30 minutes running on the battery. Given my experience there is zero chance I could have fixed this on the side of the road: I didn't have a spare or the porsche key to hold the pulley mount, or the 24mm wrench, etc in the car. FOR THE FUTURE: I will in the future I will add those things to my tool kit onboard. If the bolts behave the same then I still won't be able to change on roadside but a reasonable mechanic out in the boonies could help me if I have the belt and tools, without having to locate a porsche shop on the road.

now off to find new bolts!

IXLR8

The Reserve Capacity (RC) of the battery, listed in minutes, will tell you how long you can run.

Reserve Capacity (RC): The time in minutes that a new fully charged battery can deliver 25 amps at 80°F (26.7°C) at a voltage greater than or equal to 1.75 volts per cell (10.5V in a 6 cell, 12V battery).

I'm glad I had a new East Penn 648 battery when my alternator belt went some 110 miles from home. I started my stopwatch and picked up the pace a bit. Made it home with the battery at 11.4V which was put on charge immediately.