Master Brake Cylinder

tropical36 wrote:

Gjac wrote:

tropical36 wrote:

gutfelt wrote:
worked on lots of brakes over the years never heard of a brake line collapsing internally guess it could happen but rare

Look for it to eventually happen on the front end of an old P32 chassis.
The 97,98 and 99 have different hoses and are hard to find.
The good ones cost money, too.
Best to replace them, ahead of time, instead of waiting for it to happen and maybe lock up and ruin the pad and rotor.
Biggest problem with an internal collapse, is with the fluid not returning to the master cylinder.

If you look at these flexible rubber brake lines for the P-30 chassis you will see the line is attached to the frame through a steel support that surrounds the hose. What happens is the rubber line swells with time and has no place to go because it is surrounded by the steel support tube. The ID gets smaller acting like a check valve. A sign that this is happening is that the MH will pull in the opposite direction of the failing hose when the brakes are applied. This is quite common on the P-30 chassis.

Interesting explanation and never gave much thought to the cause.
Are the earlier models, which are much different, having the same problem?

All the hoses I have seen have been from the 90's, not sure how the earlier ones were supported. I never had this problem with hoses on cars or vans that were just rubber hoses without the metal bracket surrounding the line. Some people report the rubber disintegrates from the inside but I have not see it on my old cars without the metal flange.