Issue installing 929 Master Cylinder
 

So I ordered the a reman 929 master cylinder from Mazda Comp and had it installed 2 days ago. It looks like it is leaking where the reservoir mates to the master as illustrated in the attached pics. Notice the slight blue residual brake fluid accumulated.

It is not overflow brake fluid. I cleaned the area with brake fluid and went out for a drive. Checked it this morning and I see the residual brake fluid again at that joint.

Anyone ever experience this?

From what I can tell the reservoir is just pushed in and is held in place by some pressure fitting. Would this be a problem with the master cylinder or a problem with the reservoir?

Thanks for the help.

highlighted the leak area in red

There's a rubber gasket there I believe... probably tweaked/torn, or there's a small crack in the resovoir.

i noticed on the old master that there is a rubber gasket press fit into it. is there a gasket on the reservoir also? are these gaskets replaceable or do i need to buy another MC and reservoir?

Thanks.

I had the same problem, remove your old seals from your original master and put them in the 929 master....problem solved.

I'll give it a shot.

If anyone else experienced this, please do continue to share.

Thanks all.

I got a mazda reman master cylinder from Malloy and it had the same problem. But i had already sent back my original master cylinder. I took a super big zip tie and tied the reservoir to the master cylinder. And the leak stopped. Its been about a year and its still leak free. Not the best solution, but i did not have a choice. Mazda does nto sell the seals. I think the company that mazda uses to reman the master cylinders are using the wrong size seals.

I used my original RX-7 seal with my 929 master, too. IIRC, it just seemed like the seal in the 929 master was not a good match for the RX-7 reservoir. I don't know if it was that the seal in my reman 929 master was a lousy aftermaket replacement, but I would guess not. It seems more likely that the RX-7 and 929 seals are just different, and that you have to use the RX-7 seal with the RX-7 reservoir.

-Max

Thanks gents. I haven't had a chance to do anything further with it. The leak is very small and the car is driveable. I'll get around to it after Turkey Day.

On another note, I popped my hood yesterday after I pulled into the garage and heard a hissing sound from the master/booster area... Got to do figure out what that was.