Brake caliper pistons - need to compress!!!

[samcoombes]

On the 325, did one side no problem, but I cant get the other to shift at all. Tried everything I can think of. Anyone know of any other methods?

Thanks

[karlp]

Try releasing the bleed screw, placing on a small piece of wood then use another piece of wood the other side of the caliper and tap lightly with hammer. Beware that fluid will come out of the bleed screw.
Obviously make sure no air goes into the caliper or safer optioin is to bleed it slightly.

Karl

[smithy318i]

I always find brute force usually works.

If your bleed nipple is fcuked then

loosen the cap on the filler bottle
put the top pin back in the caliper, rotate upward, place a small (thin) piece of wood in the gap and jam a claw hammer between them, then pull (hard)

you could try some PTFE on the piston too (WD40)

[E30Adam]

Get a G-clamp on the piston and wind it back in, easy!

[Turbo-Brown]

Never, EVER use WD40 or any other type of grease or oil on brake components!

It perishes the seals leaving you with no brakes!

You can get a special lube from lockheed and the like which doesn't harm the seals, but it's more for assembly than getting stuff going again.

[smithy318i]

It perishes the seals leaving you with no brakes!

I was told the oposite! oil based lubricants protect the rubber components.

any other views?

[Turbo-Brown]

Oil may well protect rubber components like oil seals, but you try soaking a seal from the brake or clutch system in WD40 or oil and it will swell up and then fall apart

There are special lubricants for use in the brake system for a reason!

Sorry if I sound a bit harsh, but I've seen a few people recommend using WD40 on braking systems and it's a fcuking massive no-no!

[Brianmoooore]

Oil seals and the like are neoprene, not rubber.
Rubber (as used in brake components) is attacked by mineral oil and similar.
As turbobrown says, keep oil and brake components apart.

You should always open the bleed nipple on a caliper when you retract the piston. If you don't, it forces dirty brake fluid back into the system, can invert the seals on the master cylinder, and on some makes of car, will damage the ABS unit.

[johnono]

Get a G-clamp on the piston and wind it back in, easy!

did that, and it was soooo easy compared to all the other idiot methods we tried first

[Adammcf]

I just took mine off and forced the piston in by pushing really hard on it with the end of a hammer.

[hoshy]

I did my pads on Friday. I used the wheel brace... just wedged it in there and pushed

[Adammcf]

LOL! I tried that one too but the end wasnt very friendly for pushing against so the hammers flat edge worked better.