Datsun Roadster Forum-311s.org

So I have an extra brake caliper with the 2 cylinders which have been sitting in a parts box, and one cylinder was separated but the other was not. I tried the air compressor method for separation but it did not work.
Any other ideas on how to separate the piston from the cylinder?
I wanted to see what it looked like for possible resleeving. Yes I know you can get them new.
TIA,
Linda

Linda,
Soak with penetrating of your choice (inside and outside) and than try the air again.
Sometimes you can break it loose by pushing it in first or tap lightly on the side of the cylinder with a hammer.
If that doesn't work, it’s JUNK.
Be very careful using air as it can become a projectile (especially if it's stuck).

Phil
If you need more cylinders because you don't have four that can be repaired email me as I think I have some extras.

A good penetrant might do it. I'd try to fill the cylinder through the port and give the body of the caliper a smack with a nylon hammer. It might take a few days soaking. If that doesn't do any good, I'd try heat (like a propane torch) on the body of the caliper.

I had one guy tell me that he put a stuck wheel cylinder in a baggie full of atf and let it soak for a week. Piston came out with a sharp rap with a hammer.

Good luck.
Dan

Tim waltz suggested a bearing splitter to pull the cylinder out. Picture included. I did not try it as the air hose worked. When I had mine popped, I wrapped an old shirt losely around the caliper and then placed it on a hunk of carpet and lightly held it down. The air blew the caliper off the cylinder and didn't damage anything. I would definitely try the penetrating oil or the bearing puller.

Well the ATF seemed to work, along with prying and tapping. The air hose did not even though it built up pressure. Here is a photo. Interestingly the seal inside seemed to be very good, still pliable. This cylinder was stored and dry for at least 18 years. It would be interesting to know if it is a candidate for resleeving, not sure how "good" it has to be. The pin is bent, no surprise, but they can be straightened, so i am told.
This was at least a 4 on the Water Pump Removal scale......

Linda

thanks Phil for the parts offer, hopefully my brakes will be good and I should know this weekend.

It looks like the pin is bent which renders it no good. Rebuilding brakes is something best left to professionals as making a mistake can be costly.

Ross
sports imports

It looks like the pin is bent which renders it no good. Rebuilding brakes is something best left to professionals as making a mistake can be costly.

A pro? What fun is that? LOL
Don't worry Ross, if they need to be rebuilt by a pro they will be.

Linda

I speak from experience unfortunately (I was 20 at the time and knew it all). I replace calipers but I refuse to rebuild them. The hard part is putting them back together without bending the pin.

Ross
sports imports

The racers remove the pin. I wonder how that would work on the street.

I was told that the pin is only there to allow the caliper to retract properly. I am not sure how exactly it does that. Bill pulls the pins on his race car, he told me that the major difference is that the brakes are a lot louder and might not be preferable for street usage. Otherwise, they should work fine. I managed to bend the crap out of my first rebuilt caliper as I rushed the job. The other three went together fairly well after Bill demo'd how to do it. Take your time if you do it your self! Don't use a vise!

Update:
The cylinder pictured can be rebuilt.
The 4 on the car that came off today do not want to separate (naturally) so they are marinating in the ATF. I will see what they look like soon, hopefully. Well, my definition of "soon" LOL

Linda

Linda:

Let us know if you find somebody who can rebuild these. I took a set off my 68 1600 20 years ago and replaced them. I took one apart way back then and bent the pin similar to your photo. The other three I was able to pop off several weeks ago using compressed air and they look good.

Shannon

I had mine re-sleeved by Carl Jaeger in Canada. I believe he still does it and one had a bent pin which he fixed.

I had mine re-sleeved by Sierra Specialty Automotive in California. Not real cheap but very well done. They guarantee them for life against rusting.

There are some pictures on their website:
http://brakecylinder.com/" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;

When I bought my car the front brakes didn't work at all. I tried simply rebuilding them but they were pitted too badly to seal well.
Here is a picture of one of mine when I got them back.

It looks like they used brass, but that could be the color settings on the monitor. While brass is fine, it is not as durable as stainless. How much is not cheap?