How do I remove pistons from the caliper?

[montoya_fan01]

pre 6/72 production date RWC's are expensive compared to post 6/72 RWC.

As Lance says, if the piston is THAT stuck, the aluminum RWC bore is almost certainly trash.

MSA carries the ones you need, and I'm sure that other places do also, but I've never been able to get one from a NAPA, Autozone, Carquest etc for an "early" 240.

Good Luck in your quest.

[montoya_fan01]

On opposing piston brakes it would. I can't remember what the stock 240s are as I don't have them anymore.

OK, I'll bite, how would the "bolt trick" force the piston out on the opposite side of the caliper? I can see how the bolt might press one piston out, but I don't see how it can affect the piston on the other side of the caliper (the one it cannot come into contact with).

[Mat M]

OK, I'll bite, how would the "bolt trick" force the piston out on the opposite side of the caliper? I can see how the bolt might press one piston out, but I don't see how it can affect the piston on the other side of the caliper (the one it cannot come into contact with).

I'm with Montoya_fan01, especially when the piston in seated in the cylinder all the way in.

[ZSaint]

Lets see If I can figure this situation out... If you seal (plug the brake line hole) the caliper after filling it with fluid, when you press in on one puck it will hydraulic the other puck forcing it out. How does this sound? It's the only answer I can come up with. Is that what you had in mind?

[montoya_fan01]

Lets see If I can figure this situation out... If you seal (plug the brake line hole) the caliper after filling it with fluid, when you press in on one puck it will hydraulic the other puck forcing it out. How does this sound? It's the only answer I can come up with. Is that what you had in mind?

Yeah, I s'pose that could work to remove the opposing piston, but at that point I think you still have to do the bolt trick to remove the other one, IMO you'd be expending more effort than you would by simply using air pressure and keeping your pinkys out of harms way.

But hey, different strokes for different folks. I like to do things the easiest way I can find that doesn't damage parts. (my parts, or the car's parts)

[Mat M]

I apologize, I was speaking in terms of the rear wheel cylinder tear down. There is only one "piston" to speak of.

[=Enigma=]

This bolt thing simply won't work on the early 240Z calipers. Take my word for it. The pressure fitting bore does not go all the way through to the rear of the piston. At the bottom of the thread bore the circumference narrows to 1/16 of an inch or so. Only enough for fluid to pass, not a bolt. At any rate, there's not enough fluid capacity in there to push out either piston. Compressed air IS the way to go in this case. Period.

[2003z]

OK, I'll bite, how would the "bolt trick" force the piston out on the opposite side of the caliper? I can see how the bolt might press one piston out, but I don't see how it can affect the piston on the other side of the caliper (the one it cannot come into contact with).

I meant to say it "wouldn't". It works on single piston brakes though. typo on my part.

[Zedrally]

This bolt thing simply won't work on the early 240Z calipers. Take my word for it. The pressure fitting bore does not go all the way through to the rear of the piston. At the bottom of the thread bore the circumference narrows to 1/16 of an inch or so. Only enough for fluid to pass, not a bolt. At any rate, there's not enough fluid capacity in there to push out either piston. Compressed air IS the way to go in this case. Period.

I think you have looked at it from the wrong perspective.

Consider it this way, firstly if the caliper bore is full of fluid topped to the brim, so to speak. The screwing of a suitable bolt into the thread will actually force the piston free by hydraulic pressure. Assuming of course that the bolt can actually be screwed into the nipple, I've just looked at a front caliper and it appears that on the face of it it, this would work.

MOM

[montoya_fan01]

I think you have looked at it from the wrong perspective.

Consider it this way, firstly if the caliper bore is full of fluid topped to the brim, so to speak. The screwing of a suitable bolt into the thread will actually force the piston free by hydraulic pressure. Assuming of course that the bolt can actually be screwed into the nipple, I've just looked at a front caliper and it appears that on the face of it it, this would work.

MOM

It may force one or both pistons "free"; but you'll still only be able to get one of the two pistons out (by manipulating a piston back into the caliper body you'll force the opposite piston outward enough to be removed) and you'll still have one piston recessed in the caliper body that you will not be able to remove.

A I R

Simple, Easy, Fast, DONE. (meanwhile some guys are still dicking around with bolts, locating fittings, filling calipers with fluid, etc.)

[2003z]

Not everyone has air.

I do use air myself, but I have also used the bolt on a brake that had a leaky seal. It was not a 240z brake though. I was just offering another possible solution, not trying to start a huge debate!

[montoya_fan01]

compressed air is available at many neighbors, auto shops , and gas stations, (perhaps at one near you?) But one needs to make a tiny bit of effort to look for it and ask for the favor of using it. I haven't had a problem getting access to it for the 5 minutes it takes to get-r-done. just don't bother them when they are busy.