1986 Brake Booster
Thread Starter
Burning Brakes
Joined: Oct 2010
Posts: 1,037
Likes: 28
From: Montclair New Jersey
1986 Brake Booster
I have a 1986 auto. I recently have a hard brake pedal. I can stop the car but; its not right. I did replace the booster valve and rubber line going to the intake. The problem is still there.
I have two questions....I would like to get the best booster available because I hate doing anything twice. Does anyone have a suggestion on a reputable manufacture for a booster? I haven't checked GM yet to see if its still available.
Second.....Are there any short cuts or tricks that would make the job easier. Also, is there anything I should know before starting the job? It doesn't look like fun. A lot of on my back upside down.
Any help would be appreciated and or information.
Thanks...
I have two questions....I would like to get the best booster available because I hate doing anything twice. Does anyone have a suggestion on a reputable manufacture for a booster? I haven't checked GM yet to see if its still available.
Second.....Are there any short cuts or tricks that would make the job easier. Also, is there anything I should know before starting the job? It doesn't look like fun. A lot of on my back upside down.
Any help would be appreciated and or information.
Thanks...
Thread Starter
Burning Brakes
Joined: Oct 2010
Posts: 1,037
Likes: 28
From: Montclair New Jersey
Melting Slicks
Joined: May 2014
Posts: 2,891
Likes: 591
From: New Port Richey FL
A supplier that's debatable and I will leave that to the masses I put one in my car from auto zone with a self destructive installation mistake (my bad) that caused it to fail with in a year and they replaced it no questions asked and it is still working may years later.
. What makes the job easier a long 1/4" swivel socket extension about 12 to 15" is needed to reach fire wall, stacking extensions is ok.
. Now the mistake not to be made you have the booster in your happy your done with the under dash, when fitting the Master cylinder make sure the cylinder slides all the way to seated with little to no effort, I made the mistake of seating the last 1/4"-1/8" with bolts all was good for About 8 months then the booster cracked and it needed replacement. So if it binds a bit dremmle the Master if needed. It's unfortunate that most booster are plastic .
. What makes the job easier a long 1/4" swivel socket extension about 12 to 15" is needed to reach fire wall, stacking extensions is ok.
. Now the mistake not to be made you have the booster in your happy your done with the under dash, when fitting the Master cylinder make sure the cylinder slides all the way to seated with little to no effort, I made the mistake of seating the last 1/4"-1/8" with bolts all was good for About 8 months then the booster cracked and it needed replacement. So if it binds a bit dremmle the Master if needed. It's unfortunate that most booster are plastic .
Last edited by s carter; Oct 15, 2021 at 07:08 PM.
Thread Starter
Burning Brakes
Joined: Oct 2010
Posts: 1,037
Likes: 28
From: Montclair New Jersey
Ok....when I had time I was able to investigate a little. When I press the brake pedal I hear an air leak sound from inside the car. It was hard to hear with the car running this afternoon. I also noticed my rpm's are up 100-150 over normal. I am assuming because of the vacuum leak from the booster.
Melting Slicks
Joined: May 2014
Posts: 2,891
Likes: 591
From: New Port Richey FL
Ok....when I had time I was able to investigate a little. When I press the brake pedal I hear an air leak sound from inside the car. It was hard to hear with the car running this afternoon. I also noticed my rpm's are up 100-150 over normal. I am assuming because of the vacuum leak from the booster.
Last edited by s carter; Oct 15, 2021 at 08:43 PM.
Thread Starter
Burning Brakes
Joined: Oct 2010
Posts: 1,037
Likes: 28
From: Montclair New Jersey
Drifting
Joined: Feb 2016
Posts: 1,384
Likes: 339
From: Simi Valley CA
I just bought a 92 with hard brake pedal and high idle. I found a post where the guy recommended clamping the hose that goes to the brake booster. If the idle drops to normal while clamped it is 100% the booster. I tried on mine. Clamped the line, idle went down. Released clamp, idle went up.
I did the booster on my 89 and it wasn't the booster that was bad. It was my ABS pump. I didn't try that test then, but my 89 idled fine. I did take out the driver seat to do the booster and that made it a lot easier. Seat comes out real easy and the brake plunger is high up under the dash.
Checking the abs is not easy. Unless you have the specific scan tool for the abs it isn't possible to pull the codes. If it is the abs you should have the brake light on all the time.
I did the booster on my 89 and it wasn't the booster that was bad. It was my ABS pump. I didn't try that test then, but my 89 idled fine. I did take out the driver seat to do the booster and that made it a lot easier. Seat comes out real easy and the brake plunger is high up under the dash.
Checking the abs is not easy. Unless you have the specific scan tool for the abs it isn't possible to pull the codes. If it is the abs you should have the brake light on all the time.
Last edited by topfuel67; Oct 17, 2021 at 02:37 AM. Reason: Car info
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