Leaking Brake Master Cylinder?

[mx54life]

Hi so I am about to commence my build when I noticed on my recipient car that below the area where the brake master cylinder enters the brake booster is a trace of rust which appears to be a history of brake fluid leak. Is there a gasket that needs to be replaced or is this an indication that the master cylinder or the brake booster needs to changed? I have no prior info on the car as I got the car with out engine and tranny. Thanks in advance for your input guys.

http://i1284.photobucket.com/albums/a578/ebaradas/IMG_1842_zpsbge6xghb.jpg (http://s1284.photobucket.com/user/ebaradas/media/IMG_1842_zpsbge6xghb.jpg.html)

[kung fu jesus]

Brake cylinder needs to be replaced for sure. I hd the same issue years ago. I can't remember if I replaced the booster or just checked, cleaned and painted it.

[mx54life]

Thanks. Do you guys use AutoZone for reconditioned parts? Reason I ask is that they offer lifetime warranty on their parts. So I am thinking I may as well order a booster since it is so accessible without the dash and all.

[kung fu jesus]

I used AZ, but it leaked again. Woolery sold me a new OEM one he had that was polished.

[mx54life]

So the leaking is due to the brake cylinder or the booster?

[BoBo]

I usually buy my stuff at Rosenthal Arlington Mazda online. But I'm pretty sure NAPA sells decent stuff. I would just replace both master cylinder and booster and be done with it. At a minimum I would do the master cylinder first. The job can be tedious that's why I would recommend to replace both components.

[WASABI]

This (along with rusty rockers) seems to be a universal issue with Miatas. I have seen more Miatas with rust on the booster, and even more with spots of rust on the section underneath the booster. Both of my cars had it. I replaced the booster with an OEM part from Arizona (eBay).

[mx54life]

So I guess might as well upgrade the brake MC and booster now ay? lol

Let me read on this 1" MC upgrade..........

[kung fu jesus]

The MC wears out, then leaks past the piston into the booster. The Miata MC is 'interesting'. The reservoir is just snapped in there, so if you replace your MC, sometimes you need to swap over the reservoir, too. Also, if the MC doesn't come with the reservoir grommets/bushings, you'll need those, too, so just make sure you get everything you need. Bench bleed it, some replacements are more sensitive that others.

+1 on the 1" MC upgrade. I saw that and it made me lean forward in my seat to look at it.