sanchez

On my recent trip to Pennsylvania for the holidays, I noticed some moisture in the driver's carpet. I attributed this to snow on my shoes and didn't think much about it at the time.

SURPRISE! That moisture was brake fluid leaking out of my master cylinder, through a hole in the front trunk into the footwell. My carpet is saturated and some of the paint on the body floor has begun to peel. What a mess!

I took a look today and the leak seems to coming from the clear plastic nipple, grommet, and tube just below the fluid reservoir (there are two: one for each set of brakes).

Can I rebuild or replace this nipple/seal or do I have to buy another master cylinder? One year seems like a short lifespan. Unfortunately, the original part was included with the purchase of the car, so I have no receipt or warranty.

Any ideas?

sanchez

Bump

Larry Harris

Todd,
Brakes scare me for many reasons, especially a Pantera I once had. I would take the car to a Porsche mechanic and him do what was necessary to bring the brakes up to a safety standard you can LIVE with.

Larry Harris

dawgster

The leak is coming from the inner piston seal and the master cylinder needs to be rebuilt or replaced with a new or pro rebuilt unit. The usual advice is to not bother with rebuilding it yourself due to the harsh outcome if a mistake is made in the repair work. I did successfully rebuild mine on a '75. The brakes work fine and I got a good hard pedal by using the manual bleeding instructions in the Pelican tech articles. I do continue to frequently check the brake fluid level and pull back the floor board to monitor for leaks. That's a good idea anyway. It gives you an opportunity to keep dirt vacuumed out of the pedal cluster.

pjc

It is possible to purchase a master cylinder referb kit but my recommendation would be to replace. As has already been said - safety is paramount and brakes are key.

PJC

Steve Zitelli

I replaced mine a few years ago.I got a new oem ate master from Vertex in Florida for $99.I think the last issue of Panorama had them on sale for $89.It was pretty straight forward but I had to replace a few brake lines that wouldn't come off.

sanchez

Thanks for the info. I replaced the master cylinder about 1 year ago with a factory part. Unfortunately, this part came with the car as part of the purchase and I have no warranty. Given this short life, I thought a seal might have worked itself loose and could be remedied w/o replacement. I'll just order another one and replace it.

Noel

Todd,

I had a similar issue just after I installed a new master cylinder in my SC a couple years ago. The plastic piece didn't seat right in the master cylinder and fluid was seeming from that area. I pulled out the plastic hose connector and found that it had a crack in it from the reinstallation process. Purchased a new one at the dealer for about $5 and it no longer leaks.

It would be very unusual for a new MS to fail within a year.

Good luck.

Noel

sanchez

Noel,

I thought it should last more than 1 year as well. I really need to remove the master cylinder and take a closer look. Unfortunately, the 911 has become my daily driver. I'm putting a new clutch in the RX-7 next week, and after that I'll have time to look into the problem w/ the Porsche.

By the way, I used to live in the 'burgh. Yinz get donton ta see da Stillers?

Tom Mat

I have 77 911 and I experienced brake pedal fade at the beginning of this past summer. The cause turned out to be the inner seals in the master cylinder. I replaced the master cylinder. This was my first experience with doing this job and I can say that it was not to difficult and turned out to be a very satisfying repair job. The total repair cost me about $130 and that included purchasing a Power Bleeder for the brakes.

If you decide to do it I recommend that you get a couple reference articles. I used Pelican Parts and the information in 101 projects for your Porsche. Both were helpful and to the point. Take your time, don't rush and you find that removing the cylinder is straight forward. Use a good torque wrench when puttting the unit back in place. The power bleeder worked great for bleeding the brakes when everything was back in place. It is a very doable job.

Tom Mat

Bill Gregory

If the plugs and grommets are truly leaking, and not the master cylinder innards themselves, the grommets are Porsche part 911.355.922.00, and the two plastic plugs are 911.355.323.00 (front) and 911.355.322.00 (rear).