Topic: Sigh..."caliper rewind tool" for a brake job...

[rrocket]

Went to do a brake job on the Audi TT, since it's a bit squeaky in the back.  Got some Hawk HPS pads...$57 shipped. Not too shabby!  Anyways...I start the job thinking it will be a basic job.  Negative, Ghost Rider.   It seems the drunken Audi engineers have struck again!!  I need a special tool to "rewind" the calipers.  Unlike "normal" calipers that you push back, the Audi ones have to be screwed back.  So you need this special tool to affix to the piston with 2 bosses and then you screw it back in so you can put the pads on.  Sigh.  Despite having a very well stocked garage, I was stuck.  Project aborted. 

Before long, I'm going to have several hundred dollars in special tools just to be able to do basic maintenance on this car.  Ah...the joys of owning German...(NOT!!!)

[johngenx]

My C-Class was crazy simple to work on, but I hear that MB has gone away from making DIY friendly cars.  I could replace the pads and discs myself in about an hour, including taking time for a beer, uh, I mean sandwich, mid-job...   

[rrocket]

My C-Class was crazy simple to work on, but I hear that MB has gone away from making DIY friendly cars.  I could replace the pads and discs myself in about an hour, including taking time for a beer, uh, I mean sandwich, mid-job...   

The TT is the most backwards car I've worked on thus far.  And I've worked on quite a few.

BTW...here's the rewind tool.  I tired using a snap ring spanner, but no luck.  The holes aren't really deep in the cylinder to really "grab" it well.

[Flinter]

That's crazy... so the piston actually twists when it is being pushed back in the bore??  Wonder why...must be something to do with the seal around the piston??

[rrocket]

That's crazy... so the piston actually twists when it is being pushed back in the bore??  Wonder why...must be something to do with the seal around the piston??

Yes, it twists.

[Flinter]

That's crazy... so the piston actually twists when it is being pushed back in the bore??  Wonder why...must be something to do with the seal around the piston??

Yes, it twists.

Thanks, wasn't sure if I was understanding what was going on there.

[rrocket]

That's crazy... so the piston actually twists when it is being pushed back in the bore??  Wonder why...must be something to do with the seal around the piston??

Yes, it twists.

Thanks, wasn't sure if I was understanding what was going on there.

I understand what's going on, but still don't understand WHY it needs to be going on....

[aquadorhj]

so, did you get the tool, or what?     i thought i saw the brake tool kits at auto parts store.   it was a doozy the first time i had Audi A6 brake to do.

[blur911]

I've had these stupid things on everything from a Ford Probe to my present Audi 90.  Stupid design, I wish they had gone with the smaller drum type parking brakes.

Anyhow, I've managed to turn these things in using a C-clamp to press the piston in while turning the edge of the piston with a pair of channel-loks and a bit of patience. YMMV

[safristi]

..don't be such a toolRrocket grab some of Johnx's "sandwiches"...burp.............that's the way those germains do it...screw it till it hertz a govenia.........

[ktm525]

You didn't have a brake cube? These cubes are about $15 and are multi fit for the above pistons you describe. Yours looks much fancier. Anyhow my understanding was these ratcheting pistons are because they also act as the parking brake (?). In designs that don't have the ratcheting there is typically an inner drum for the mini parking brake shoes.

I could be full of it though...

[HeliDriver]

That's also how the rear pistons worked on my Civic - they screwed in and out of the bore.

But, Honda was thoughtful enough to cut a crossed pair of grooves into the piston's face so it was easy to turn them with a screwdriver shaft stuck in lengthwise.

[wing]

What ktm said.  My S2000 has the same design.  I think I paid $3 at princess auto for a cube, you put it in a ratchet and away you go.

[Railton]

That's also how the rear pistons worked on my Civic - they screwed in and out of the bore.

But, Honda was thoughtful enough to cut a crossed pair of grooves into the piston's face so it was easy to turn them with a screwdriver shaft stuck in lengthwise.

Same with Mitsubishi - I used the biggest flat screwdriver in the tool box to turn them back in on a pad/shim replacement job.
Railton

[HeliDriver]

So... it seems that Ford, Honda and Mitsubishi engineers were all drunk on the job, too.

Sounds like a fun job. 

[rrocket]

That's also how the rear pistons worked on my Civic - they screwed in and out of the bore.

But, Honda was thoughtful enough to cut a crossed pair of grooves into the piston's face so it was easy to turn them with a screwdriver shaft stuck in lengthwise.

Exactly.  I've seen cars with them in the past, but you could turn them with a screwdriver...or some other tool in the box.  Not the case with the Audi.  This will be the 3rd-4th tool I've had to buy for routine maintenance.

[dr_spock]

I made one myself using a $3 cube from princess auto and a dremel cutting disc to remove a couple of the pins on the cube so it fits.   Compress and turn...

[rrocket]

I made one myself using a $3 cube from princess auto and a dremel cutting disc to remove a couple of the pins on the cube so it fits.   Compress and turn...

Oh I thought about that.  But it should not have to come to that.....Poor design.

[jamie1]

Any car that uses the caliper for braking and a park brake uses this design.  Sometimes you can use a pair of needle nose pliers. Lots of times you do need the special tool, because of the force needed just to start the turning process.

[rrocket]

Any car that uses the caliper for braking and a park brake uses this design.  Sometimes you can use a pair of needle nose pliers. Lots of times you do need the special tool, because of the force needed just to start the turning process.

The other one's I've worked on have deep cross pattern so you can use an allen key, screw driver, etc to turn it in.  Not so with this design.