So I just completed the replacement of the upper control arms on my Audi. The UCA pinch bolt is a known villain in the Audi/VW community. Being a steel bolt living in an Aluminum world awash in road salt and grime, it often gets hellishly stuck. So much so that a german comany called Klann makes a $2K
extractor tool (Klann KL-0250-41 KA).
But a can of Aero-Kroil and an $8 harbor freight heat gun and a ball peen hammer got it done.
Method:
Step 1 heat the aluminum housing for about 2 minutes with highest setting of heat gun (HF says it's 1000 deg, whatever, it's hot)
Step 2 spray with aero kroil (there are several places in the aluminum housing you can shoot the kroil down into to get along the length of the bolt, I hit them all).
Step three: tap the bolt head and the housing a few times from various angles with the ball peen (don't get crazy, just enough to get some vibrations going)
Step four: (optional) drink a beer
Step five: remove bolt with a 16mm boxed end wrench and a 16mm ratchet, might need to tap it out with a flat head under the bolt head and rubber mallet, but it comes out easily, you may have to squirt a little more kroil while tapping it out.
But a can of Aero-Kroil and an $8 harbor freight heat gun and a ball peen hammer got it done.
Method:
Step 1 heat the aluminum housing for about 2 minutes with highest setting of heat gun (HF says it's 1000 deg, whatever, it's hot)
Step 2 spray with aero kroil (there are several places in the aluminum housing you can shoot the kroil down into to get along the length of the bolt, I hit them all).
Step three: tap the bolt head and the housing a few times from various angles with the ball peen (don't get crazy, just enough to get some vibrations going)
Step four: (optional) drink a beer
Step five: remove bolt with a 16mm boxed end wrench and a 16mm ratchet, might need to tap it out with a flat head under the bolt head and rubber mallet, but it comes out easily, you may have to squirt a little more kroil while tapping it out.