Brakes!!

[MADMAX]

Allright Fellas! I know that this issue has been debated to death-BUT-I am going there anyway. I have a 71 FJ40 with mini-truck converted front discs and a JT Outfitters rear disc conversion. It still has a stock master cylinder & booster. The booster I know is CRAP, but it is a new booster. The problem I have is a very hard pedal, with virtually no play @ the top. I have new OEM pads, and freshly ground rotors, but still have to use a ton of foot pressure to stop, especially if I need to stop in a hurry. I also do have an aftermarket adjustable proportioning valve for the rear discs. I am not not neccesarily looking for a dirt cheap deal, or used parts. I just simply want to know what is the best way to get the brakes to perform the way they should. Do I need a booster/master combo--if so lay it on me! Which is the best, which one provides the most assistance etc. Thanks for your help!!

 

[Downey]

Then my guess is you are running this without a booster??? If that is the case, you would be prudent to in fact add a booster (Pickup or Landcruiser), and of course the best choice is 1976-newer (dual diaphram).

 

[MADMAX]

The booster is hanging there, but apparently does not work. I installed this booster just a few weeks ago, but it made little if any difference over the one I replaced. I am pretty sure it also is defective, as it makes no difference in the pedal when I start the engine and also the idle changes because of a vacuum leak when I apply light pedal pressure. Am I better off replacing the M/C also, or is the stock sufficient? Do you guys sell the booster you mentioned?

 

[Pin_Head]

Start by adjusting the pedal rod to specs so you have the proper free play. The gap between the booster rod and the master cylinder piston is also critical. Make sure the booster is working; sounds like it isn't.

 

[MADMAX]

Pin_Head,
Do you have those specs available? I adjusted them exactly as they were on the original stuff, but do not know if that is correct. That still would not correct the problem of little to no assist-correct?