Brake cylinder replacement

[Brett Voigt]

While looking at the brake cylinder on my 69' 912, it looks rather rusty. The last I drove it, it did not brake amazingly, but it also wasn't that bad. I attributed most of that to the old rotors/pads, air in brake lines and need for general caliper rebuild. I think I'm going to replace all the brake lines while I have the front end apart and also switch out the rubber lines for some steal braided. What should I be looking for with the brake cylinder in terms of how good/reliable it will be? It's kind of pricey, but when it comes down to it, I do not want all of my hard work to end up smashed into a brick wall because I was too cheap to change out a $250 cylinder. Also, what sort of skill level/tools does it require?

[Jaems]

I think the 69 had a duel brake cylinder. If not replace it with one. I had the front left front caliber blowout this last Summer. If I hadn't replaced my single with a duel. I would have had no brakes at all, with the exception of the emergency brake.

I had this happen before about 25 years ago. I had to drive 120 miles on the freeway with only the emergency brake. So I replaced the single with a duel.

To replaced the lines (they all come as straight lines), you will need a tube tool to bend the lines to the shape of the ones you are replacing. The rubber lines are usually the first to go. I replaced mine about 25 years ago with the steel braided ones.

Because I have had caliber failures in the pass and drive rather spiritedly . I use ones that are rebuilt by professionals. I had one go out in the first 200 after it was rebuilt in a garage. It takes a couple hundred hundred miles to break in the new brake pads.

[Brett Voigt]

Just looking at the ATE and URO replacement part options for the cylinder, it says its a dual circuit. I'll take some pics of the master cylinder tomorrow to show what it looks like. As for the brake lines, pelican has pre-bent lines both in galvanized and regular steel. My prior set lasted 45 years so I think Im gona go with the non-galvanized.

[Jaems]

Just remember, you need to flush your brake fluid once a year. I usually do mine in the Spring with a oil and filters change, before the annual driving season.

[Cobra06]

They now make pre-made and formed complete brake line sets for the 912, saves lots of time and bending.
In fact for a bit more than the master cylinder a conversion kit with everything you need is available from certain vendors, not sure if our host has them but worth a check

[cmpski]

Go with ATE parts if you can.
Chris

[Cobra06]

Originally Posted by cmpski

Go with ATE parts if you can.
Chris

Second-that, I would stay away from URO, and stick with the ATE.

[Brett Voigt]

I think the fact that I even need to ask if I need a new brake master cylinder necessitates that it's bad enough that I should just by a new one and get it over with. Either way... I finally got around to taking some pics of the cylinder. Sounds like the ATE version is the way to go. I'm going to replace the brake hard lines as well and get some steel brake lines (cuz why not at this point).

[IMG][/IMG]

[IMG][/IMG]

As a side note, I picked up a set of Brembo calipers from an 80's Alfa that have the 3" bolt spacing to fit the 69' strut housing. The pistons are 48mm and fit larger pads and the vented SC rotors I picked them up off a guy on an Alfa forum who rebuilds em' for fun. Anodized gold, new seals, came with new pads and mounting hardware... Can't wait to put them on.

[IMG][/IMG]