axl911

I'm trying to swap out my rear brake rotor and pad.

How do you remove the caliper? Are the caliper being held on by 11mm hex bolts (on the side) instead of the 10mm as shown on this web page?

http://p-car.com/diy/brakepads/

thanks,
anthony

joey bagadonuts

Part #12 is the lower bolt but I'm not sure of the size ... anyone? (yes, this is a picture of the front caliper but it's very similar). From www.msroadrace.com

darth

Hi Anthony

I've got a 90C2 and the rear calipers are held in place by 2X 10mm allen head bolts (i.e. one needs a 10mm hex wrench to remove it). Bolt #12 in your diagram corresponds to the lower one. The corresponding upper flange in your diagram (i.e. where a bolt is absent) is where the second allen head bolt is located. The series of what looks likes washers and spacers part #14, 15, 21, 22 - I have no idea why they're there. The front calipers are similar but are held in with 2X 17mm (I think?) hex head bolts. Again the 17mm corresponds to the size wrench needed.

Once you have the calipers removed the rotors are held in by 2X phillips head screws (i.e part #2).

Hope this helps
Bill
90C2

axl911

Oh boy. I just checked mine. How can you access the lower one. There is a hole in the trailing arm, but where can you get a long enough hex bolt socket to fit?

Arjan B.

Go to Autozone or Sears to bu a fitting tool. Please clean the inside of the bolt first, otherwise the wrench will turn around and will damage your bolt.

darth

I cut off a long allen wrench just before the 90 degree bend and insert it into a 10mm socket/ratchet.

Bill
90C2

Bill Gregory

In my area, neither Autozone or Sears carries the extended hex socket requred. You can use a standard hex key to take it off, however, you really need a socketed version to torque it properly when you reinstall it. I believe I got my fitting from Performance Products. Don't forget they have a standard 15% discount for PCA members, too.

JasonAndreas

I finally gave up and bought the proper extra long 10mm 3/8" socket driver from a Snap-On truck. The price was a little expensive (around $17USD) but definitely worth it (and I didn't want to wait another 2 days for a part to showup via FedEx). The part numbers are FAML10E (socket) and FAML10E2 (bit)

axl911

I got made a 10mm allen head socket from my allen head key. But the bottom bolt is still stuck even with my electric impact wrench.

Is it safe to take a torch to the caliper?

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anthony

darth

Anthony

Applying heat would be my last choice after applying liquid wrench but if you have to you have to. Just keep in mind there are rubber seals around the pistons and if they get too hot they'll deform. Rather than the impact wrench have you tried more leverage with just a wrench?

Hope this helps
Bill

Jeff Curtis

Axle, is it STUCK...or is it STRIPPED??

If it's just stuck, take a punch that's long enough to make it through the hole in the trailing arm and tap into the center of the allen key hole...this will send vibrations throughout the bolt and possibly jar some corrosion that is making it so difficult to remove said bolt.

DO NOT use your Impact Wrench on this bolt!!

NO allen bolt or allen key was designed for an impact and you will pound out the hex shape to where the bolt will be next to impossible to remove!

I used my BIG torque wrench when I popped mine loose for the first time...it was a BI***, believe me.

I would hold off on the applying heat idea for now, if the bolt is stripped...you've got some creative fenagling to do!

Axle911 - WHERE are you located?? ...please at least update your "location" in your profile, it's FUN to know where people are from! (you too Darth).

Reason I'm curious is because A LOT of us on here would give advice like "go to Sears or Pep Boys" and we have no clue where you live so we're giving blind advice.

FWIW, I saw LONG Metric Allen sockets at Pep Boys, but didn't buy them because they were only 3/8" drive...ordered one from Snap-On thinking it was 1/2" drive and wound up with a $25 3/8" drive 10mm allen when I couldn've had a whole damned set and LUNCH for that amount.

Flyin Elvis

Drench the daylights out of it with brake cleaner, do it twice over a half hour. It is a better penetrant than WD and works better. I agree with Darth re torching.

axl911

I've soaked the bolt with PB Blaster and WD40. Don't think it works too well since there is a lock washer on the bolt which prevents the pentrating fluid from penentrating.

The bolt is just stuck, not stripped yet. I am being very careful to do anything that would strip it. If it does, I would cry since there is virtually no access.

I've cut off my Sears 10mm hex wrench and insert it to a shorter 10mm hex socket to create a longer one. The Sears hex actually fits the caliper bolt well with minimal play.

I've tried using various methods from my big 1/2 inch drive, breaker bar, to using a jack to leverage the 1/2 inch drive. None worked so far as the lenght of the hex wrench (3.5 inches) would distort and possibly strip the bolt.

I think the problem here is the lenght of the hex socket allows the allen head to twist (lateraly and radially) and not transfering the force to the bolt. Because of that, I will try 2 things. 1) use a 10mm closed end wrench at the point where the hex key mates with the bolt to put pressure on the socket/bolt while using the breaker bar (or last resort the impact wrench.) 2) buy another 10mm long hex wrench from Sears. Cut of the short end L so the wrench would fit snugly up against the bolt and use a breaker bar.

I don't think heat would work here since the bottom bolt is near the hard line connecting the 2 sides of the caliper. I may boil fluids and fry seals if I apply heat.

I will also tap the hex socket when it is inserted into the bolt as Jeff suggested. I can use the hex socket instead a punch right?

Oh, I also updated my profile to reflect my location.

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anthony

warmfuzzies

One more trick, try tightening the allen bolt first, an old trick I learnt as an apprentice.

Kevin

darth

Anthony

You'd be suprised how much torque can be applied to the allen head bolt - Porsche has used some really good hardware where needed. If you keep the allen wrench seated in the bolt well and don't go off center when applying force the allen wrench may twist but that torque will be transmitted to the bolt - just as long as you don't go off center on the allen wrench it won't break at least not the kind of torque a normal person can apply with a 2ft. breaker bar. A little known fact about WD40 - it is a cleaner with a small amount of lubricant which evaporates after which one is left with 2 very clean surfaces to rub/wear against each other - use a proper penetrating oil to loosen bolts - sometimes soaking it for days is required - it will get in. I know that's a tough couple of days especially when you want the bolt removed NOW!
Another trick similar to what Jeff suggested is to take a center punch or chisel type and hitting the side of the bolt head tangentially in the direction which will loosen the bolt

Hope this helps
Bill
90C2