Write-Up: Brake Master Cylinder - Install & Bench Bleed

nvsteve wrote:

I just replaced MC.  I didn't see how I could bench bleed it since fluid just runs out the tube in the reservoir that connects to the rubber hose (I guess that's for the ABS?).  So I bolted the MC in place, then used the bench bleed kit as described using the brake pedal to actuate the cylinder.  Worked out ok.  I guess if you could plug the bottom of that reservoir tube you could bench bleed the MC but seems easier to do it after bolted on to the car.

Next is replace warped front rotors.  Pads are still good,  can I use them after rotors are replaced?

To bench bleed any master cylinder, you hook up both lines and feed them back into the reservoir. Then actuate the master cylinder several times either in a vice or on the car with the brake pedal. Some MC come with plastic lines and fittings for that purpose.

Larry,

If you look at the master cylinder you'll see the reservoir has a tube at the bottom that connects to a rubber hose. If you put fluid in the resrvoir with the hose disconnected, fluid runs out of the tube so you can't bench bleed it unless you plug the tube somehow. So I used the bench bleeder kit with the plastic lines and fittings, but I just did it with the brake pedal after installing the MC and connecting the hose to the reservoir.

Still on my original master cylinder at 157,000. I'll have to take a look. Whatever you did must have worked if your brakes work.

Has anyone tried upgrading to the 06+ Impala (Police Package) master cylinder/brake pedal?

Apparently the Impala MC has a larger bore to move more fluid, and the brake pedal assembly is shorter. Might be something to consider for the people who upgraded to f-bodies.

1996 Riv has brake pedal that when pressed it very slowly goes downward and I have to keep my distance from car in front when at a stop.  If I take my foot off and put it back down again it is better.  Seems no vacuum leak and wondering what else could be causing this problem. Can't figure out how to start this in a new post, but hopefully someone will see it and reply. Thanks for any help you can offer!

BatMobile wrote:

1996 Riv has brake pedal that when pressed it very slowly goes downward and I have to keep my distance from car in front when at a stop.  If I take my foot off and put it back down again it is better.  Seems no vacuum leak and wondering what else could be causing this problem. Can't figure out how to start this in a new post, but hopefully someone will see it and reply.  Thanks for any help you can offer!

Could be caused by a worn master cylinder. Not that much $$ for the part but some $$$ labor to replace because you have to bleed it before installing it. A remanufactured one is OK and in some ways preferable.

Moderator: can you move this to an appropriate brake thread?