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Discussion Starter #1 (Edited)
Ok so I know this isn't a hard repair, but I didn't find one before so I thought I'd make one.

My brake booster was bad, I could hear the booster hissing whenever I hit the brake pedal, so I replaced it. I plan to do the one ton upgrade, but right now I'm just trying to get it roadworthy first.

It was an extremely easy repair. I had the opposite of most people in that my camera didn't have a good battery until I put it back together, so everything here is new. (I put the pics up in reverse order so it'll seem normal.)

Here are the tools I used, a pair of pliers, a 14mm socket, and a ratchet. I did end up using an extension, but it isn't mandatory.



The first step is to remove the vacuum hose line to the booster. You can use the pliers to remove the clamp. You should also take the top nut off the right side of the brake booster holding the hydraulic lines to the brake booster stud.



The next step is to remove the two nuts holding on the master cylinder, and pull the cylinder out of the way. Be careful not to bend any of the steel lines.



Once off it should look like this:



Go under the dash, remove the pin that connects the booster to the brake pedal. You will see the pin, then the brake switch around the arm from the brake booster, a plastic washer and then the brake pedal.

Remove the four nuts connecting the brake booster to the firewall.



Remove the brake booster from the outside of the firewall. It's okay if the plastic that goes through the firewall breaks on you, mine included a new one.


Once you have it off, you should be able to put it all back together the way you took it off. Read the below post from Dave's bronc 90 before reassembly.
 

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You should probably also mention that adjusting that rod on the front of the brake booster that pushes into the master cylinder is very important. You want it just touching the master cylinder piston when the master cylinder is bolted in place, but not compressing it at all. This take up any slack that might be there, and an improperly adjusted rod is often the cause of poor brake pedal feel.
 

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Discussion Starter #3
Thanks!
 

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Also it's great to test the MB by seeing if it holds vacuum with the engine turned off. Most of these booster issues are from worn seals.
 

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Discussion Starter #5
I figured mine was. It had sat for what I believe to be a year, so seal are going to be a problem, dried up cracked seals.
 

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You should probably also mention that adjusting that rod on the front of the brake booster that pushes into the master cylinder is very important. You want it just touching the master cylinder piston when the master cylinder is bolted in place, but not compressing it at all. This take up any slack that might be there, and an improperly adjusted rod is often the cause of poor brake pedal feel.

Good write up teasers, I believe my brakes have gone soft because of the seals but to clarify your recommendation Dave,

I am assuming keep it simple and put something into it and measure it's depth by feeling it touch the master cylinder?

(btw, it was very hard finding the right words to not make that question sound naughty)
 

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Sorry to rejuvenate an old post, but I am trying to adjust my brake booster push rod and I can't seem to get it right. I slowly adjusted it out 1/4 turn at a time. Now I have a great pedal, but when I jack up the front end and spin the tires I can hear the brakes dragging a little bit. Then when I back it in just a little, the brakes dont drag, but pedal feels week. Is it bad to have the brakes drag just a tad? The fronts spin no problem but drag just a tad and backs spin freely no problem or drag. What is the correct position to have the push rod set?
 
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