brake problem

[cgreen]

I am using the 88-98 power booster and master for my disc upgrade on my 1965. I have bench bled the master with no issues. however, once mounted on the booster, I get nothing. bad booster maybe?

[Jurassic-1]

If you have a hard pedal even with vacuum going to the booster it may be a bad one.

[cgreen]

thanks for the reply. I am getting nothing. no pedal, no pressure, nothing. I disassembled lines and tried to get fluid straight from master while applying pedal and get nothing. remove master and can bench bleed no problem. not sure what is going on here.

[luvbowties]

Originally Posted by cgreen

thanks for the reply. I am getting nothing. no pedal, no pressure, nothing. I disassembled lines and tried to get fluid straight from master while applying pedal and get nothing. remove master and can bench bleed no problem. not sure what is going on here.

Take a look at this.
Sam
Re: 72 with Power Brakes Question
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Quote:
Originally Posted by rn2fine
Regarding 72's or other years with power brakes has anyone had any experience with either using or not using a spacer (looks like a bullet) fitting into the rear of a master cylinder piston. Have all new brake parts, entire system, and pedal goes to floor. A local classic Chevy parts store gave me a spacer to put into the back of the master cylinder. Just wondering if anyone has used the same. Thanks.
See pics: one has a void! Just for interesting information: A company called getdiscbrakes.com makes a plug(their part #MCBUL01), kinda shaped like a bullet, to fill this void. I've actually never seen a mfg'd one, as we had already learned to make them, to go between wrongly-paired booster-and-m/c, for several years before I knew anybody actually made such an animal. We made them simply, using the non-threaded portion of a bolt, and grinding-and-shaping to loosely reside in the void/pocket. BUT I'D ADVISE TO NOT USE A PLUG FOR PEDAL-TO-MC--BUT ONLY FOR BOOSTER-TO-MC, AS NOTHING MUCH WOULD ENSURE ITS REMAINING IN PLACE IF POSITIONED BETWEEN BR-PEDAL AND MC!!!
HTH,
sam
Attached Images

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Last edited by luvbowties; 02-17-2013 at 06:47 AM. Reason: grmr

[poorboy]

What year master are you using? Masters do not all have the same depth hole for the pushrod.

[cgreen]

The master and booster were supposed to be a set from the same 98 Chevy truck. I didn't pull it though so I cannot confirm that. They were separate when I picked them up. Guess I should take them apart and see if I need that spacer. Thanks for all the input guys!

[Captainfab]

The correct name for this 'spacer' is the intermediate pushrod. It does sound to me that the intermediate pushrod is missing, and that is causing your issue. Without the intermediate pushrod, there is no transfer of movement from the pedal and booster to the master cylinder. And since you said that the booster and master were separated when you got them, it could have easily fallen out of the booster. If you have trouble finding one locally, let me know.