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Suainie
12-22-2015, 01:58 PM
I have a 59 Skyliner that had been off the road for over 12 years when I purchased it last February. Needless to say I have encountered many problems due to the car not being used for such a long time. The problem I am dealing with now is the fact that I have virtually no braking power and I have replaced all the wheel cylinders, hoses and brake shoes. The car does have the power brake booster and I removed the master cylinder today and besides being full of crud I find that it is a 1" bore master cylinder which I believe is incorrect for the power brakes. It is my understanding that the power brakes required a master cylinder with a 1 1/8" bore. I recall reading somewhere that the push rod was also a different length but I am unable to locate where I found that information. Can someone know the correct length of the push rod for the different master cylinders. I had a feeling that perhaps someone had replaced the master cylinder at some time not realizing there was a difference. I cannot find any source for a replacement master cylinder with the larger bore - is it possible to remove the power brake booster and use the standard master cylinder? Thanks for any help.
Harold

Ford Only
12-24-2015, 05:03 PM
Unless for some reason you need to be factory correct, you should go to Summit Racing or Jegs & purchase a master cylinder/power brake booster combo.
You would need to do some brake line plumbing but you will have a much safer car with a dual master cylinder.
I have used both 1" and 1-1/8" master cylinders and never noticed any difference, if the brake pedal doesn't bottom out on the floor the rod you have should work, you should have just a little clearance when the pedal is pushed all the way down.
You need to do this test with a brake line loose so the is no hydraulic pressure against the pedal.
If the rod is too long it will just make the pedal higher, the adjustment for master cylinder to the power brake booster is on the front of the booster and it is real important that that clearance is correct