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what can cause this leakage?
dr-fastlane - 8/2/09 at 09:10 PM

What can cause the next problem. When building my car I’ve changed the master brake cylinder for a new one. After one year it began to leak between the cylinder housing and sealing rubber. To get it on the road as soon as possible. I changed the leaking master cylinder for a new second one, from the same manufacturer (not original ford). And also the fluid reservoir. Now after again one year later it’s leaking again at the same place. Between the Reservoir and sealing rubbers it’s dry, no leaking there.
When I prise out one of the sealing rubbers, the inside of the cylinder housing was rusted. But only at the place where the seals where sitting.

Has someone a idea what can cause this leaking?

Gr. Roy Rescued attachment brakecylinder.JPG
Rescued attachment brakecylinder.JPG


k33ts - 8/2/09 at 09:35 PM

now ive seen the pictures im barking up the wrong tree

[Edited on 8/2/09 by k33ts]


austin man - 8/2/09 at 10:38 PM

quality of brake fluid or poor quality of refurbishment. Brake fluid attracts moisture. U should consider going back to the supplier as the units may be poor quality 1 failure is unluck 2 would point at the reconditioning process


DIY Si - 8/2/09 at 10:39 PM

Is the reservoir pushed fully in? They can sometime take a fair shove to get them 100% seated. Or is anything pushing against it at all? Is it possible for it to move under a heavy pedal and rub against anything on the bulkhead?


dr-fastlane - 9/2/09 at 06:04 PM

No, the reservoir is free from everything, nothing pushing to it . I have contact the manufacturer and they say it’s my fault. When replacing the old for a new mastercylinder, I should had used new seals. But the new cylinder came with new seals and they where already fitted. So I think, maybay the leaking is caused by the poor quality.

The brake fluid was renewed one year ago, when replacing the first mastercylinder. To bleed it, I used the Gunson-easy-bleed, nothing wrong with that.

[Edited on 9/2/09 by dr-fastlane]


Ninehigh - 9/2/09 at 09:44 PM

What kind of brake fluid was it, and how well are the brakes working with the leak?


dr-fastlane - 10/2/09 at 07:12 PM

It's normal dot4 brake fluid. The brakes where working fine before this leaking appeared. Just like the previous time the problem starts when the car isn’t used for while, winter season.


Ninehigh - 10/2/09 at 07:21 PM

Ok so now there is the leak how are the brakes? I mean are they really soft or does the really hard pedal mean there's nothing else going on?


dr-fastlane - 10/2/09 at 07:51 PM

The pedal feels really hard, such it should be

Have been thinking, because the brakes work fine. And I could find a way to clean up the inside rusted spots nicely. Than I could refit the sealing rubbers with some “ate” grease. Think the manufacturer of the MC put in the sealing rubbers dry. When the car isn’t used this time of year. The bare metal under the seals has time to rust with the help of the corrosive brake fluid. The ate grease will prevent corrosion. Would this be a good idea?