I have a brake problem. I put new brake shoes, hoses, wheel cylinders, and master cylinder on this car and bleed them. Bled the master cylinder also. But still have a problem with the brake pedal going to the floor after it sits overnight. There is no leaks anywhere in the brake system that I can see. I was just wandering if there was something I overlooked when I did this brake job. Any one have and ideas on what I might have missed Thanks in advance rab1969
If you pump it up 3-4 times and hold it firmly, does it start out at the top and slowly drop? Or does it only go down after sitting overnight? Are you're brake shoes adjusted out all the way to match up with your drums? Do you have drums all the way around? You can eliminate the wheels by clamping the three rubber hoses off over night. I have a brake hose clamp made for this but you can use a pair of vise grips as long as you use a couple of pieces of wood such as pieces of paint mixing sticks. You would not want to clamp the hoses directly with the vise grips. Would likely damage them. If you clamp all three hoses (2 front 1 rear) and the pedal still falls the next day the problem would definitely be in the mc.
Did you bench bleed the master cyl or bleed it on the car??? If you bled it on the car you may have damaged it. (A full pedal stroke on a dry master cyl can damage the pistons) allways bench bleed em. Are you loosing fluid??? if so Look for leakes at all the lines/fittings that you touched first. Gotta tell yah...Sounds like a bad master cyl. Either bad out of the box or damged by improper bleeding process. Good luck!!!
Oh no not another rebuilt master. Sorry just a pet peeve of mine. We dont install them at work anymore. Had too many fail too quickly over the years. IS it a REBUILD??? Check the rest of the system over but dont rule out your new master cylinder. Never assume a new part is a good part.
I seen a lot of cheap auto part stores MC (and fuel pumps) be bad out of the box or need replaced a month later. I been lucky with Napa parts.
I have found the only way I like to bleed brakes is with a pressure bleeder. I made one like a Motive unit and put 15 lbs of pressure in it and could just watch the fluid move perfectly. You just watch the fluid get cleaner and then move to the next cyl or disc. The rule of thumb is to start at the farthest wheel but my question is what differents does it made if you have a dual MC ? I did the fronts first and then the rears because the fronts I could watch the bleeder gauge better.
I agree. I don't know wheter he used a rebuilt unit. It is possible to get a bad new unit but I believe the chances are much less w/ a new unit. Im not in the trades but over the years I have found new units works best when u can find them. Two things I never buy rebuilts when I can get a new unit -master cylinders and water pumps. Not worth the hassle of re-doing for a few extra dollars. I believe the problem is in the Master, whether it may have been damaged in the bleed process or defective frm the box. JMO.
I've done the hose clamping thing, too, but you need to be careful 'cause nowadays some brake hoses are Teflon lined and clamping can crack the Teflon.
Just wanted to thank everyone for their help. Looks like it was a rebuilt mc problem got a bad one learned my lesson on that one. Thanks again
