power brake booster replacement

grumpyvette

Administrator
Staff member
http://www.ecklers.com/product.asp?pf_i ... pt_id=1068

http://www.popularmechanics.com/automot ... 13448.html

http://www.mamotorworks.com/corvette-19 ... -3994.html

c4booster.png


boosterl1.gif

boosterl2.gif

boosterl5.GIF

boosterl3.jpg

boosterl4.jpg

power-brake3.jpg

c4booster1.png

fr3994.jpg


first theres metal replacements that are stronger than the original plastic ones (above)

its a fairly strait forward procedure, step one

get the factory shop manual and read it, theres an extensive section on the brakes and booster repairs but the plastic booster in my opinion is a bad idea and replacing it with the metal boosters a plus



before replacing a booster try to verify its bad..

If your car has cruise control and many do, check the vacuum line switch on the brake pedal. There is a large vacuum line attached to it. It's job is to disengage the cruise control every time you hit the brake. REMEMBER the problem needs to be isolated before it can be repaired,It could be the source of your vacuum leak, check the line from the booster to the intake and check the booster fittings
unbolt the master cylinder from the booster, theres no need to remove the brake lines from the master cylinder. but if you do feel the need to do that use a tubing wrench and remember youll need to bleed the brakes in most cases.

carefully watch,exactly what parts go where durring the dis-assembly and re-assembly process,

slide the drivers seat fully to the rear and , now for the fun part, youll need to just about stand on your head but theres a clevis pin on the brake pedal that needs to be removed , and the two nuts that hold the booster in the firewall need to come off, and the booster pulls out, pay attention to the switch that controls the brake lights as its easy to damage

If the master cylinder or ABS modulator has been replaced, or there is air in either unit, the ABS modulator will have to be bled using a specific procedure. On the older GM applications with the Powermaster III ABS system, here’s the recommended procedure:

1. To bleed the isolation valves in the modulator, there are two bleeder screws. Start with the one toward the engine. Turn the ignition on and apply light pressure on the brake pedal. Open the bleeder screw and allow the fluid to flow until clear. Close the screw and do the same at the second bleeder screw.

2. Depressurize the accumulator by pumping the pedal 40 times with the key off. Wait about two minutes for the brake fluid to de-aerate, then refill the fluid reservoir with DOT 3 brake fluid.

3. Now you can bleed the boost section. This is done by applying moderate pressure on the brake pedal and turning the ignition on for three seconds, then off. Repeat this a total of 10 times. Make sure the pedal feels firm when you have finished, and give the car a road test to make sure the brakes are working properly.

Note: There is also a “solenoid bleed test” option you can use if you have a Tech 1 scan tool. This will cycle the hold and release solenoids to purge air from the booster.
 
Last edited by a moderator:
Back
Top