bills928

I'm in the process of rebuilding the front calipers of my 84. I have them all apart and ready for reassembly with new seal and dust boot, I am reading in the manual where the piston must be rotated to 20 degrees, how does one determine where 20 degrees is ? ... Are there marks that line up the piston with the housing? What is the reason for the 20 degrees ?.

Thanks for the help
Bill

Mrmerlin

if you can post a few pictures of your calipers and the pistons, what your asking for can be explained

GlenL

The notch in the piston faces into the direction of rotor turning...if that's the question.

bills928

Merlin ..... Here are some picts of the piston and housing..... I'm assuming that the notch in the piston lines up with something on the housing ???

GlenL

61

Ad0911

The answer is in the WSM Vol. IV repairgoup 46 page 6 and rpairgroup 47 page 11. It has a picture showing how the piston is supposed to be aligned in the caliper, with rotation of the disc shown with arrows

bills928

Thanks .......I found it.
So what is the reason for the notch? I've never seen a caliper piston like that before .

Ad0911

Different calipers use different techniques to get the same result: slightly angled position of the brakepad for better bite? Perhaps also to make the pad retract a tiny amount after braking to rlieve them from the disc

Rob Edwards

Yes, am sitting at a kid activity, paying rapt attention.

Ad0911

[QUOTE=Rob Edwards;11772285]Yes, am sitting at a kid activity, paying rapt attention./QUOTE]

I would never have guessed that overhauling brake calipers could be a fun activity at a kids party, but what the heck, as long as they enjoy thmselves. Perhaps painting the car could be the thing for the girls? Flowers and all. Take me back to '69!

Bilal928S4

Is this also true for the S4 brakes also?

Rob Edwards

AFAIK there is no directionality to the 4-pot calipers' pistons.

Ad0911

I think (my guess) that this function is incorperated in the damping plates. But I have never seen the 4 pot caliper on the inside, nor have I seen the damping plates. But I have seen this on other cars.

Mrmerlin

I grabbed this from another page

Ad0911

I recognize thisas the procedure for the rearbrakes. Correct?