74 Brake Booster Replacement
Thread Starter
Instructor
Joined: Aug 2004
Posts: 166
Likes: 0
74 Brake Booster Replacement
Any tips on getting access to the 4 bolts that hold the brake booster to the firewall? I see there is what looks like an access panel in the cowl area, but I can not get if off even with all 4 bolts removed from the panel.
Any tips would be appreciated.
Any tips would be appreciated.
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
That access panel won't get you closer to those bolts. They are your pedal assembly.
You have to contort yourself under the dash, with a ratchet, a few long extensions, a wobble, and a deep wall socket.
It's a pain in the butt for sure but it can be done as listed above.
What's the reason behind taking out the booster? Make absolutely sure it needs to come out before going to all the trouble.
Safety Car
Joined: Aug 2001
Posts: 4,883
Likes: 11
From: North Easton Mass
Remove the driver seat for more room and lie on your back. If you have a removeable rear window take it out so you can rest your legs on the rear panel. You will need an extension, a couple universals connected together for some flexibility and a deep socket, but tape them up so they don't flop around. Stuff some towels behind the carpet so the nuts that you drop don't get lost. If you have a manual trans there is a very tiny clip that has to be removed from the neutral switch, and I found it easier to unbolt the switch for more access to the upper nut.
It takes quite a while to get the nuts off and the new ones on, so you will either have to put extra beer on the passenger seat or have an assistant to keep you supplied.
Rick B.
It takes quite a while to get the nuts off and the new ones on, so you will either have to put extra beer on the passenger seat or have an assistant to keep you supplied.
Rick B.
Drifting
Joined: Jan 2002
Posts: 1,645
Likes: 11
From: Schaumburg IL
Brake Booster Replacement
I have replaced several on 72-74's and there is not an easy 
way. I have found that when all things are considered I drop the steering column and pull the dash pod (just mark the wires and watch the grounds) and the access is much easier.
To take the old one out I use a saws all with a thin metal cutting blade and cust the bolts in the engine compartment. Does not really damage the firewall if careful. Then inside you can get to the rod on the brake peddle easier with the pod removed. Besides if give you a chance to replace tose dim or burnt out bulbs and clean and lube the tach and speedo.
Now the secret to get the new one it - get your boy or borrow one that has the small hands and arms and have them start the bolts on the 4 posts inside. Then you can finish the job with the extensions.
Questions - Are you sure the PSB is bad?? If you don't have a super hard or collapsing peddle, maybe the brake bleed or the MC are at fault??
way. I have found that when all things are considered I drop the steering column and pull the dash pod (just mark the wires and watch the grounds) and the access is much easier. To take the old one out I use a saws all with a thin metal cutting blade and cust the bolts in the engine compartment. Does not really damage the firewall if careful. Then inside you can get to the rod on the brake peddle easier with the pod removed. Besides if give you a chance to replace tose dim or burnt out bulbs and clean and lube the tach and speedo.
Now the secret to get the new one it - get your boy or borrow one that has the small hands and arms and have them start the bolts on the 4 posts inside. Then you can finish the job with the extensions.
Questions - Are you sure the PSB is bad?? If you don't have a super hard or collapsing peddle, maybe the brake bleed or the MC are at fault??
Thread Starter
Instructor
Joined: Aug 2004
Posts: 166
Likes: 0
Thanks everyone. I got it just as everyone described. I know the PB was bad because it had no boost and when the vacuum was connected it created a leak. Pull the line, put a finger over the check valve, no more vacuum leak.
Thanks again. Now does any one know where I can get a reliable replacement?
Thanks again. Now does any one know where I can get a reliable replacement?
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
Burning Brakes
Joined: Oct 2006
Posts: 1,006
Likes: 28
From: Lutz Florida
Thanks everyone. I got it just as everyone described. I know the PB was bad because it had no boost and when the vacuum was connected it created a leak. Pull the line, put a finger over the check valve, no more vacuum leak.
Thanks again. Now does any one know where I can get a reliable replacement?
Thanks again. Now does any one know where I can get a reliable replacement?
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Thanks everyone. I got it just as everyone described. I know the PB was bad because it had no boost and when the vacuum was connected it created a leak. Pull the line, put a finger over the check valve, no more vacuum leak.
Thanks again. Now does any one know where I can get a reliable replacement?
Thanks again. Now does any one know where I can get a reliable replacement?
Since you're going through the horrible pleasure of pulling out the brake booster, have you considered replacing it with a hydraulic power brake booster that's run off of the power steering system instead of the vacuum system?
It's a smaller unit, it looks better in my opinion, cost isn't too much more than a vacuum unit, and installation is all done from the outside of the car minus the pedal pin.
PM me your email address if you want a ZIP file with the info I have on Hydroboost.
Drifting
Joined: Aug 2007
Posts: 1,924
Likes: 6
a deep 9/16ths 3/8 drive socket a 3/8 drive universal and a variety pack of extensions and an air ratchet
the clevis pin clip will test your patience. try not to lose it. Corvette Central sells the wrong clip as the right clip. try not to lose it
remove the seat
being a contortionist helps
did I mention the clevis pin clip?
the clevis pin clip will test your patience. try not to lose it. Corvette Central sells the wrong clip as the right clip. try not to lose it
remove the seat
being a contortionist helps
did I mention the clevis pin clip?
