I just joined today, and in appreciation for all the help I've gotten from this site by using the infamous search button, I'll contribute to this forum by sharing my experience on getting this job done in my '87 stang.
Tools needed: 3/8 ratchet, 3/8 universal extension, at least a foot worth of 3/8 extensions, 9/16 deep socket, pair of pliers, philip screw driver to remove under dash panel and expose steering column further, 9/16 wrench, long tube to increase torque leverage, 7/16 or 1/2 socket (can't remember now, sorry), flashlight, music in the garage, baby hands, flexible wrists, & several Motrin 800mg tablets.
As many fox owners realize, our cars are over 20 years old, and many original parts are getting to their final years of usefulness.
At this point, I'm not really sure how long the brake booster plastic diaphragm had been leaking, but just last week after my 50 mile commute, i turned off the radio & listened to a vacuum leak which I would describe as a hiss that was fairly faint, but once the brake pedal was depressed, it became much more noticeable. It's just hard to listen to vacuum leaks when a pair of Alpine Type R Subs are filling the cabin with back massaging low bass tunes.
I was hoping that the leak originated from an old hose attached to the cruise control vacuum dump valve attached in front of the brake pedal, and spare me the brake booster replacement, but I'm just not that lucky. And I do realize that this booster was placed in Detroit back in 1/1987, so it's been there 24 years already.
Once I got underneath the dash, it was pretty obvious that the hiss was emanating from the brake booster. Car was still stoping, and with the engine off, the brake pedal still moved further back after dumping all the vacuum & turning engine on again. I also disconnected vacuum line feeding the booster from the intake manifold, and I was a bit upset to HEAR no vacuum leak at all. I had no idle problems which leads me to believe that the booster was still mostly functional, but it was just a matter of time before I would've ended up behind someone's rear bumper!
Procedure:
1. Unscrew nut securing the brake line manifold attached to the strut tower. The manifold is located right underneath the master cylinder. You'll see the nut behind the left front wheel. It would help if you turn wheels all the way to the left to open up more space.
2. Remove both 9/16 nuts securing master cylinder to booster. They were pretty tight, so I had to use a 9/16 wrench and a long handle adjustable wrench to be able to apply more torque. Careful here that you don't end up braking the master cylinder fluid reservoir. It's a really delicate plastic reservoir which is being held to the master cylinder by a prayer!
3. Pull master cylinder away from booster. Maker sure back of master cylinder is dry. This will ensure that your booster wasn't ruined by a fluid leak from your master cylinder. Although the metal brake lines are somewhat flexible, we still need to be fairly careful to not kink the lines. I was able to do this job without having to disconnect the brake lines, which saved me the effort of not having to bleed all wheels toward the end.
4. Disconnect Vacuum hose to brake booster.
5. Inside car, push driver chair all the way back. I'm 5'9'' & 160 lbs, and my back is till hurting, but it still beats having to pay someone several hundred dollars for a job a mechanically inclined person can do himself or for political correctness...herself as well!
6. Remove the under dash panel closest to the firewall underneath the steering column. It just needs the removal of two philip screws and set panel aside.
7. With pliers, position yourself under brake pedal with flash light, and locate the red hair pin holding booster rod to brake pedal. Once hair pin is removed, you'll see a white plastic bushing that will come off. Save it, because the new kit doesn't come with them. The brake light switch attached to the booster rod will come off once the rod is off the brake pedal. You'll also notice a second bushing (black) inside the circular opening at the end of the booster rod. Do not lose this bushing either!
8. With the rod out of the way, now you can start praying for patience, & remove the four 9/16 nuts holding the booster to the firewall. The worst one is the right upper nut. The only way I could get it out was by using many 3/8 extensions (over 1 foot) with the 3/8 universal joint and the deep socket attached. You have to route this long set of extensions above the last steering column bracket until reaching the nut. The cruise control (CC) amplifier bracket is held to the lower left nut. See how it's attached, so you can put it back in the way it came out. Move CC amplifier bracket out of the way for now. Once all nuts are removed, it's time to get out and go to the front of the car.
9. Start pulling on the booster, being careful not to put to much stress against the master cylinder, and running the risk of kinking the metal brake lines. Remember, the booster has been there at least 20 years, it's a hell of a tight fit, and I had to use a long handle adjustable wrench to help me pry the booster off the firewall. You also need to move some wire harnesses out of the way to help you maneuver the booster off the car.
10. Assuming that your master cylinder is good to go (no leaks), then start placing new booster in. Align all four bolts through the four holes and push in as far as you can. It will not go all the way in, because as the rod touches the brake pedal, it will impede further progress.
11. At this point, it's a good idea to connect the booster rod to the brake pedal by putting the black bushing on the brake pedal first, then the brake light switch. Once the rod is nicely position in the brake pedal, take the white bushing and press it in until you're able to see the hole in which the hairpin will be inserted. Insert the hairpin in, and now is back to the front of the car again.
12. Continue pushing booster some more. I was able to push in about 90% of the length of the booster bolts. After that, I got underneath the dash again, and finished bringing the rest of the booster bolts in by screwing the four 9/16 nuts back in. Don't forget to attach the CC bracket back in its place.
13. Time to screw the two nuts holding the master cylinder back to the new booster. Attach vacuum hose to booster, and screw the smaller nut that secures the brake line manifold back to the strut tower.
At this point, I turned on the car, & the hiss was gone, but I was sore as hell. The happiest thing for me at this point was realizing that I didn't have to bleed all the lines. I tested the brakes by putting car in reverse and drive, and although the booster is a fox stock replacement, I'm noticing that it takes less effort to activate the brakes, and when the brakes do squeeze the rotors/drums, the car does come to a halt with much eagerness, so perhaps my booster was only half as efficient as it should have been.
I hope this post, although long, helps some one in need of doing this job in the future. The only thing I regret is not taking pictures as I went along, but I hope I was descriptive enough to allow anyone to follow what I did. After seeing how long this post is, i realize that it's very true that a picture is worth a thousand words!
This job took me 2 1/2 hours to do, since it was my first time. I'm sure people who work on mechanics for a living can do this in about an hour, but next time I have to do this (hopefully not too soon), it'll take me less time.
Cordially,
Phil
Tools needed: 3/8 ratchet, 3/8 universal extension, at least a foot worth of 3/8 extensions, 9/16 deep socket, pair of pliers, philip screw driver to remove under dash panel and expose steering column further, 9/16 wrench, long tube to increase torque leverage, 7/16 or 1/2 socket (can't remember now, sorry), flashlight, music in the garage, baby hands, flexible wrists, & several Motrin 800mg tablets.
As many fox owners realize, our cars are over 20 years old, and many original parts are getting to their final years of usefulness.
At this point, I'm not really sure how long the brake booster plastic diaphragm had been leaking, but just last week after my 50 mile commute, i turned off the radio & listened to a vacuum leak which I would describe as a hiss that was fairly faint, but once the brake pedal was depressed, it became much more noticeable. It's just hard to listen to vacuum leaks when a pair of Alpine Type R Subs are filling the cabin with back massaging low bass tunes.
I was hoping that the leak originated from an old hose attached to the cruise control vacuum dump valve attached in front of the brake pedal, and spare me the brake booster replacement, but I'm just not that lucky. And I do realize that this booster was placed in Detroit back in 1/1987, so it's been there 24 years already.
Once I got underneath the dash, it was pretty obvious that the hiss was emanating from the brake booster. Car was still stoping, and with the engine off, the brake pedal still moved further back after dumping all the vacuum & turning engine on again. I also disconnected vacuum line feeding the booster from the intake manifold, and I was a bit upset to HEAR no vacuum leak at all. I had no idle problems which leads me to believe that the booster was still mostly functional, but it was just a matter of time before I would've ended up behind someone's rear bumper!
Procedure:
1. Unscrew nut securing the brake line manifold attached to the strut tower. The manifold is located right underneath the master cylinder. You'll see the nut behind the left front wheel. It would help if you turn wheels all the way to the left to open up more space.
2. Remove both 9/16 nuts securing master cylinder to booster. They were pretty tight, so I had to use a 9/16 wrench and a long handle adjustable wrench to be able to apply more torque. Careful here that you don't end up braking the master cylinder fluid reservoir. It's a really delicate plastic reservoir which is being held to the master cylinder by a prayer!
3. Pull master cylinder away from booster. Maker sure back of master cylinder is dry. This will ensure that your booster wasn't ruined by a fluid leak from your master cylinder. Although the metal brake lines are somewhat flexible, we still need to be fairly careful to not kink the lines. I was able to do this job without having to disconnect the brake lines, which saved me the effort of not having to bleed all wheels toward the end.
4. Disconnect Vacuum hose to brake booster.
5. Inside car, push driver chair all the way back. I'm 5'9'' & 160 lbs, and my back is till hurting, but it still beats having to pay someone several hundred dollars for a job a mechanically inclined person can do himself or for political correctness...herself as well!
6. Remove the under dash panel closest to the firewall underneath the steering column. It just needs the removal of two philip screws and set panel aside.
7. With pliers, position yourself under brake pedal with flash light, and locate the red hair pin holding booster rod to brake pedal. Once hair pin is removed, you'll see a white plastic bushing that will come off. Save it, because the new kit doesn't come with them. The brake light switch attached to the booster rod will come off once the rod is off the brake pedal. You'll also notice a second bushing (black) inside the circular opening at the end of the booster rod. Do not lose this bushing either!
8. With the rod out of the way, now you can start praying for patience, & remove the four 9/16 nuts holding the booster to the firewall. The worst one is the right upper nut. The only way I could get it out was by using many 3/8 extensions (over 1 foot) with the 3/8 universal joint and the deep socket attached. You have to route this long set of extensions above the last steering column bracket until reaching the nut. The cruise control (CC) amplifier bracket is held to the lower left nut. See how it's attached, so you can put it back in the way it came out. Move CC amplifier bracket out of the way for now. Once all nuts are removed, it's time to get out and go to the front of the car.
9. Start pulling on the booster, being careful not to put to much stress against the master cylinder, and running the risk of kinking the metal brake lines. Remember, the booster has been there at least 20 years, it's a hell of a tight fit, and I had to use a long handle adjustable wrench to help me pry the booster off the firewall. You also need to move some wire harnesses out of the way to help you maneuver the booster off the car.
10. Assuming that your master cylinder is good to go (no leaks), then start placing new booster in. Align all four bolts through the four holes and push in as far as you can. It will not go all the way in, because as the rod touches the brake pedal, it will impede further progress.
11. At this point, it's a good idea to connect the booster rod to the brake pedal by putting the black bushing on the brake pedal first, then the brake light switch. Once the rod is nicely position in the brake pedal, take the white bushing and press it in until you're able to see the hole in which the hairpin will be inserted. Insert the hairpin in, and now is back to the front of the car again.
12. Continue pushing booster some more. I was able to push in about 90% of the length of the booster bolts. After that, I got underneath the dash again, and finished bringing the rest of the booster bolts in by screwing the four 9/16 nuts back in. Don't forget to attach the CC bracket back in its place.
13. Time to screw the two nuts holding the master cylinder back to the new booster. Attach vacuum hose to booster, and screw the smaller nut that secures the brake line manifold back to the strut tower.
At this point, I turned on the car, & the hiss was gone, but I was sore as hell. The happiest thing for me at this point was realizing that I didn't have to bleed all the lines. I tested the brakes by putting car in reverse and drive, and although the booster is a fox stock replacement, I'm noticing that it takes less effort to activate the brakes, and when the brakes do squeeze the rotors/drums, the car does come to a halt with much eagerness, so perhaps my booster was only half as efficient as it should have been.
I hope this post, although long, helps some one in need of doing this job in the future. The only thing I regret is not taking pictures as I went along, but I hope I was descriptive enough to allow anyone to follow what I did. After seeing how long this post is, i realize that it's very true that a picture is worth a thousand words!
This job took me 2 1/2 hours to do, since it was my first time. I'm sure people who work on mechanics for a living can do this in about an hour, but next time I have to do this (hopefully not too soon), it'll take me less time.
Cordially,
Phil
