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Domino
07-27-2004, 10:34 PM
I've soaked it in WD-40 for three days and spent two days on it with a 480lb/ft impact gun. It will absolutely not budge. My next move is to heat the crank pulley with a torch. My only concern is that I will destroy the crank seal. Anyone have any experiences?

therooster
07-27-2004, 11:23 PM
I did this same thing on my street Audi when changing the timing belt. Went to the local Audi dealer and asked, very nicely, how they did it. I was told to heat the Sh*t out of the bolt and take a 3/4 inch breaker with a pipe and give it all I have. Brute Force and Ignorance was the name of the game. Since then I have probably had the street car pulley off a half dozen times and my race car about a dozen with no problems. For me MAP gas works fine and I just happen to have a 3/4 inch socket set. 1/2 just will not cut it. BTW I was told by the Audi tech that a 1/2 impact wrench, no matter the lb/ft, will not take off the crank pulley.

badal
07-28-2004, 08:19 AM
If the motor is in the car, you can brace a breaker bar against something solid and use the starter torque to break it loose.

planet6racing
07-28-2004, 09:16 AM
I slide an 8' pipe over my best 1/2" breaker bar and use that. But, this only works if the engine is still in the car.

If the engine is out of the car, you're going to have to get a bigger impact gun. We've gone to a 3/4" gun on a SHO engine and that seemed to work OK.


------------------
Bill
Planet 6 Racing
bill (at) planet6racing (dot) com

Domino
07-28-2004, 09:51 PM
Thanks for all of your input! It finally broke loose. After heating the bolt with MAPP gas for a total of 20 minutes I figured it took about 532 lb/ft of torque to break it free.

Crude calculation: I can leg-press 650 lbs so that's about 325 per leg. The rails on the leg-press are about 35 degrees from vertical.

Effective rate of force = 325lbs(35Cosine) = 266lbs
266lbs * 2 foot breaker bar = 532 lb/ft

Not as much as I thought it would take. It would explain why the 475 lb/ft impact gun didn't work.