brake master

[shawnved]

Hi i got a 1962 fj40 gas

i installed a new brake master cylnder, and all new lines, and wheel cylnders.
the problem i an getting is that brake fluid will leak past the o ring in the master
cylnder and will end up on the floor of the truck. i had a jobber master cylnder,
and a oem toyota one in, the both did the same thing. any idea's would be
a great help. thanks.

 

[65swb45]

Welcome newbie. If your terminology is correct, the 'o-ring' IS your problem. The cylinder uses a cup that has a lip on one end that flares out to force the fluid in one direction, and hold it back in the other. An o-ring will provide neither.

 

[Poser]

Mark-


I had this issue on my 1969 40 before I converted the brakes to the later dual master set up...


Anyhow,

I thought that my linkage was not adjusted properly, and that I was over-acctuating the master...

Could he be 'bottoming out ' the piston in the master?


Does this make sense?

 

[65swb45]

Mark-


I had this issue on my 1969 40 before I converted the brakes to the later dual master set up...


Anyhow,

I thought that my linkage was not adjusted properly, and that I was over-acctuating the master...

Could he be 'bottoming out ' the piston in the master?


Does this make sense?

An interesting thought, but I don't think so. The bore is complete, end to end, and the part of the piston where the cup is located is far enough back in the bore that it could not 'fall' off the end of the bore.

 

[Poser]

Was thinking that the lip of the cup could be getting caught on the hole that allows fluid into the bore...


Just a thought...



I adjusted my linkage, installed a new Toyota master, and things worked fine after that...


-Steve