I'd like to replace these rusty brake caliper bolts... PET part number?

[sugarwood]

I happened to have my front tires off today.
The 4 Torx bolts and the nuts on the backside are pretty rusty.
My brake pads are pretty thick, so they won't be replaced anytime soon.
So, those bolts will be even worse by then.



I'm not able to find these 4 Torx bolts in the PET. ('86 3.2 Carrera)

911 Carrera / Turbo (1984-1986) - Brake, Front Axle (Carrera)


EDIT: Ok, those 4 bolts are permanently part of the caliper itself.
The only time the rusty bolts matter when trying to rebuild the calipers themselves, right?
Just leave it alone?

[sugarwood]

Oh, and I had 2 questions about something else in the driver's front wheel well.

What are the upper and lower tanks for?

That zip tie is creating a serious kink in the circled hose.
The kink does not show up clearly in this photo, but it's pretty big.
How concerned should I be?

[matt demaria]

Upper tank is catch tank for gas tank venting. Lower tank is windshield wiper fluid. Since that is fill line to ww tank I wouldn't be too concerned unless severely constricted.

[sugarwood]

OK, based on some further reading, it looks like those 4 caliper bolts are permanent?
They are not loosened when replacing pads, or even removing the caliper from the rotor.
So, when does one remove these 4 torx bolts? Only when rebuilding the calipers?

[Cooper911SC]

As you have figured out, those bolts hold the caliper halves together.
The bolt heads are RIBE (pronounced Reeebeee). Don't attempt to loosen with a Torx.

The bolts are only removed when doing a full caliper rebuild. They were originally coated with a black oxide type finish.

Many here on Pelican, myself included, have used the caliper restoration services of PMB Performance.
A great way to go. You'll love the results. All clean and replated!

Cooper

[matt demaria]

Pretty sure that the bolts are not torx. I believe that Porsche called them Ribe Allen. The bolts are very special and they are 10g hardness.
Try these numbers from 2.7 carrera (vented rotors)
Front 901 351 945 10 and 901 351 946 10
Rear 901 352 978 13 and 901 352 978 12
Some of the numbers do not come up; they might be NLA.

Also try Stoddard.

[47silver]

Buy a very good ribe socket set if you remove these bolts and nuts. I believe that bolts are 7mm in diameter. You will not find them at your local supply house or even McMaster Carr. I rebuilt 8 total calipers and will ship the next set to the pros

[sugarwood]

Originally Posted by Cooper911SC

As you have figured out, those bolts hold the caliper halves together.
The bolt heads are RIBE (pronounced Reeebeee). Don't attempt to loosen with a Torx.

The bolts are only removed when doing a full caliper rebuild. They were originally coated with a black oxide type finish.

Many here on Pelican, myself included, have used the caliper restoration services of PMB Performance.
A great way to go. You'll love the results. All clean and replated!

Cooper

My brakes work fine, and the rest of the caliper is in great condition, so there is no rebuild in any near future. The only time those bolts need to be removed is for a caliper rebuild. At that point, the shop rebuilding them can just Dremel off the rusted RIBI bolts, if need be. The bottom line is that I don't really need to be worried about this, correct?

[McLaren-TAG]

Originally Posted by sugarwood

Oh, and I had 2 questions about something else in the driver's front wheel well.

What are the upper and lower tanks for?

That zip tie is creating a serious kink in the circled hose.
The kink does not show up clearly in this photo, but it's pretty big.
How concerned should I be?

Don't sweat it about the kink in the hose, it's just the windshield washer fluid hose to the reservoir. Since it's low pressure as long as it flows freely enough you're good. The bottom is windshield washer, the top is an expansion tank for gas vapors as the car heats up in the tank if parked outside the vapors have a place to expand and then vent from there through to the charcoal canister in the back.

[Eric_Shea]

Caliper Geek to the Rescue!

OK, the fasteners are Ribe M9x65 and they are NLA as standard replacements. They are "absolutely" the worst fastener to get out of a caliper (well, aside from a Girling IMSA GTP caliper with hollow and turned allen head steel fasteners in aluminum bodies)

The Ribe head is too small for the task and the 14mm nut is very tall so, there's a lot of rusty/crusty thread engagement for that Ribe R6 head to overcome. Why they did it? Maybe so shadetrees won't be able to get back into them... kinda like the screws in the bathroom stalls.

The rear calipers have M7x60 and 65 fasteners with R6 heads. Earlier M-Calipers have M8x55 and 60 fasteners with a robust R8 head. These are larger M9 with R6 so... anyone reading this should tread lightly with patience, a Ribe bit set and a MAPP torch in hand. Here's the drill:

Soak them and let them sit.
Heat the nut very hot.
Lightly tap the Ribe bit into the head to make certain it's seated.
Use a long breaker and a deep well 14mm to break free. I like the manual method on these over the power tools. This way you can feel any problems as they arise.

Odd that the fasteners look so bad and the calipers look so good.