rear caliper piston thread direction

jcb

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I have B5 RS4 rear calipers on.
Can some one remind me if these are left or right hand threaded to wind them in!?

I did them last time and ended up dropping a piston as I wasn't paying attention! but I cant remember which way I wound it
 
feckers wont go it!!
they are right out as the pads are well worn and no amount of pressure and screwing is moving them in.
stupid fecking design!!

thoughts?
 
I did mine last week using a piston tool. N/S Was nice and easy to wind back. However, the O/S was a right pig!! I gave it a good soak in WD40 before trying to wind in. It was the rubber over the piston that was causing it to be like solid. Once the rubber was freed from top of piston, it went much easier but still not a easy as the N/S did.

Persevere with it and keep trying.

Or

Replace calliper?

Dan
 
If your car has the aluminium-bodied calipers then the books/workshop manuals say (I believe Haynes and ELSAWIN too) to wind the pistons in clockwise to replace pads etc?
In practice I have found this to be the wrong info?
I found that even using a proper brake piston retraction tool it was a fiddle, as you have to exert pressure on the piston (which of course with the tool makes it want to go clockwise) but at the same time turn the piston (with a big pair of mole grips or waterpump pliers) ANTI-CLOCKWISE.
This is the total opposite of what the printed materials I have so far come across all say, and to all you doubters out there,lol, I've made a written note in my car file that this is the case (I refer to it each time before I work on the car) and has worked both times I have done the job.
The trick is to apply only just enough pressure on the piston to start forcing it back in but at the same time turning it anti-clockwise; if you are really finding that you are applying LOTS of pressure to wind the piston in then something is wrong!
The handbrake mechanism don't forget acts by means of a thread on the back of this piston so don't apply excessive force when trying to get the piston back in, take it easy and it should move slowly but surely.......
Hope this helps!
 
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well I just did mine this afternoon

What a ball ache.
had to remove and completely strip the caliper removing the pistons, cleaning everything up and winding them back in empty. (clockwise for reference.

no way it was moving with any amount of wind back action!
I pulled the head off the windback tool and stuck it on an adapter on my windy gun. worked a charm.

have a lot of brake bleeding to do in the morning!!
 
well I just did mine this afternoon

What a ball ache.
had to remove and completely strip the caliper removing the pistons, cleaning everything up and winding them back in empty. (clockwise for reference.

no way it was moving with any amount of wind back action!
I pulled the head off the windback tool and stuck it on an adapter on my windy gun. worked a charm.

have a lot of brake bleeding to do in the morning!!

I've used a Draper multi-purpose brake piston cube (cut off two of the legs) on a 3/8 inch ratchet (an extension bar) before with pretty good results. The only way I can get it to work properly is to reinstall the brake carrier and floating caliper (minus the rotor and pads), then using a block of wood behind the caliper - apply my bodyweight while turning the tool. Eventually goes in. A decent pair of heavy leather gloves helps. Never tried the piston wind-back tools - I'm sure they're easier. Possibly bleeding the brake valve slightly at the same time may help? I always use a little Lockheed red grease under the dust sleeve too.