ceedee

i learned that... actually that's the reason i need a new caliper.
i broke one of em...grrrrrrr

Bill Ball

Oh, now it becomes clear. Sorry to hear that.

Rob Edwards

My turn-

I started in on front shocks tonight- I got the other three, but one of the front S4 caliper mounting bolts (10 mm hex) is stuck. Despite 30 minutes of Kroil, my impact wrench set at 90 psi wouldn't budge it, and I then snapped the bit clean off the craftsman 10 mm allen socket while trying to loosen with a 1/2" drive 18" breaker bar. Sigh. The flats in the head of the caliper bolt are beginning to deform a bit, and I'm afraid of stripping this bastard.

What's the lapping compund trick to bed the (next) socket snugly in the bolt head so it doesn't round out? Or shall I just heat the bolt? Hairdryer, heat gun, or propane torch, and for how long? (Don't want to set the caliper on fire.....)




I did make some progress, one shock is out. Took about 45 minutes once the car was in the air (thank goodness for air tools...)

heinrich

Rob, I'd post this in the official "I'd heat It" thread

Charley B

There's your problem. You're only using three jack stands per corner. .

Rob Edwards

Charley-

With all the money that I have saved by not being able to put a lift in my POS garage, I have developed quite the jackstand collection. The silver 3-leg stand is an AC Hydraulics 1.5 ton stand, of finest European quality, which I bought years ago, when I knew even less about wrenching than I do now. Too bad that its curved saddle makes it pretty much useless for anything other than duty like this......


H- how much heat? (I know, impossible to answer, but like boiling water hot, or scorch the paint with propane torch hot?)

StratfordShark

I also found the front caliper bolts were extremely tight, but I got them off using a breaker bar. I'm not Charles Atlas either so breaker bar may be weapon of choice here. I think I managed to chew up the hex socket in the bolt so filed flats on it and got it out with bolt extractor socket?

I think I remember that the problem was more getting a good angle for the bar with the car only being on axle stands. The rears were even harder to get a good angle - had to lie down and use my foot!

AO

I had to drill mine out. You want a bit that is about the size of the diameter of the shaft of the bolt (not the head), this way you shouldn't damage the caliper. Once you get down past the head, you should be able to break the head off the bolt. Then the caliper will be free and you can lift it off the shaft of the bolt.

mark kibort

I like the one under the fender nose. thats the quicky fender removal techique. forget about those 20 8mm nuts, just drop the car and the fender rips right off!

mk

mark kibort

so this is the side where the mounting bolts are not stuck and you have one left on the other side, right?

if so, you just heat the bolts with a real heat gun, or quickly with a torch. get it good and hot and focus the heat on the steel area where those bolts are stuck (below the caliper) I use the box end wrenches and give them a good wack with the hammer . heated, it should come right apart.

Mk

JHowell37

Craftsman allen sockets are **** poor quality and always break. I'm not sure why it's such an issue, but it is.

What I suggest is that when you take the socket in for replacement, get one of their "ball head" allen wrenches. You can get the traditional style with a 90 degree bend, or you can get them with a T handle. They seem to be made from much tougher steel then the sockets. Slip the box end of a 10mm combination wrench onto the allen and then insert the allen into the head of the bolt. Slide the wrench all the way down until it is up against the head of the bolt. Then try to loosen the bolt using the combination wrech. If it doesn't not come loose, I'm sure you know how to slip the box end of a second wrench over the open end of the 10mm wrench to give you extra leverage. If that works, great. If not, get out your drill.

The reason this is effective is because the allen wrench is a very weak link in the chain and most of the torque goes into twisting and distorting the tool (until it eventually breaks.) If you do it my way it takes most of the torque off the allen, so the allen doesn't distort, and more importantly it sends the torque into the bolt, thus eventually/hopefully breaking it free.

jon928se

The "allen bolts" that hold the caliper halves together, according to the WSM shouldn't be removed. But why ? When I refurbed my front calipers I ended up removing these bolts and splitting the calipers to remove the little bolts that hold the slider plates. The bolts I removed had what looked to me like optimoly TA on them.

Replacement bolts are I believe not available from Porsche or Brembo, but there is nothing special about them - Just Grade 12 Allen Head bolts, I forget the size.

Rob Edwards

Well, I got it out, but not before stripping the head. I went out and bought a heat gun yesterday, heated up the caliper mount to ~200F (by IR), and tried the good-quality 10mm T-handle hex wrench/10mm wrench on the flats/17 mm 'extender' wrench trick as described by JHowell above. This produced a nice sickening grinding feeling as the flats rounded out.

Then it occurred to me that I had won an Ebay auction a while back for some Snap-On bolt extractors:



The 7/16 bolt extractor fits nicely in a rounded out 10mm allen bolt and takes a 5/8" socket to turn it. I cranked it in place with my impact wrench, then loosened the caliper bolt with an 18" 1/2-inch breaker bar. Victory is mine!




except for the small matter of not being able to get the extractor out of the now-mooched bolt....

Lizard928

I was going to say give the head of the bolt a very solid hit with a big hammer to loosen it. But you already have it.

heinrich

Rob...