Having a hard time diagnosing my brakes on a 73 Mav. They're manual four wheel drums. The car sat for the winter and I recently replaced the right rear wheel cylinder because it had been leaking last fall. I bled the brakes in order from farthest to nearest, and the pedal still went to the floor with light resistance.. So off to the parts store for a new Master cylinder, I bench bled it and then put it in, re-bled all four corners...and right back to the same problem, pedal travels all the way to the floor with little resistance...any ideas?!? Only thing I can think of at this point is my driveway is sloped, so the car is unlevel with the front lower than the rear, would that effect the bleeding?
Been face down in the dirt all day doing the same thing you describe... Have you adjusted the push rod that goes from the pedal to the cylinder..? Robert.
How are the other wheel cylinders? Generally when you replace the wheel cylinder on one side you should do it for the other side as well. I would also check the brake hoses front and back, and the lines for any leaks. Does the MC Fluid level keep dropping? I recently had a similar issue to this happen with our Van, I ended up replacing the Master Cylinder, Rear Brake Hose (I'd already done the front two a year or two ago), and flushing the system out real good. I don't think you can adjust the Push Rod for a Manual Brake System, I replaced the MC in my Mav a few years ago and there was no place to adjust the push rod I think thats only for Power Brake Systems.
That's the odd thing, there's absolutely no fluid loss, even after pumping the brakes for a couple minutes. Had a friend pump them while I checked the right rear brake shoes for movement, which checked out fine...
also, I replaced both front wheel cylinders last fall before storing it for the winter...anyone have any similar problems like this??
Only things I can think of now would be one or more brake hoses might be swelling if thats the case just chuck all three and get new ones, you really can't go wrong replacing those esp if it's never been done or it's been a long time since it's been done. Even if they appear fine sooner or later you're going to end up doing it anyway and if something should fail it may end up costing you more $$$. Also I would check to make sure the brake shoes at all four wheels are adjusted properly, that was suggested as a possible cause for my recent problem with the Van. Also how well does your Parking Brake hold? One sure fired way to tell if a brake adjustment (at least in the back) is needed is to apply the Parking Brake and try to move the back tires. Obviously that wouldn't help with the front you'll just have to gauge that which I know can be a pain, I have a four drum system on mine too and if I had the $$$$ I would convert it to disc. Anyway you can check my thread on the problem I had here. http://mmb.maverick.to/showthread.php?t=45587 It sounds as though your problem is as perplexing as mine was
If everything else checks out I suppose that master cyl could be bad too. The sympton sure sounds like a mc.
My friend had a '79 mustang that had a similar problem. His nightmare started when the brake hose going to the rear axle was replaced. We could not get the brakes to bleed back up. After a new mastercylinder, wheel cylinders, front brake hoses, two big bottles of brake fluid and a full day of cursing and swearing we found the problem by accident. I was in the driver's seat pumping the brakes and he had just stuck his head thru the passenger window when he heard a squirting noise. Ford ran the steel line to the back brakes in through the passenger side firewall and along the floorboard by the door. Since his door and/or cowl leaked, the floor had quite a bit of rust and the carpet there was falling apart. Guess what else was rusted? That friggin brake line had a bad rusty spot there where fluid was getting out and air was getting in. We replaced the brake line and bled it again and the problem went away. My advice would be to jack the car up on all fours and get under there with a light and look at every inch of brake line for wet or rusty spots.
If the fluid did not drop when you re bled on new master cylinder, your new master cylinder is most likely bad. Watch your fluid level, also check at firewall and make sure MC is not leaking inside. Good luck
When I replaced the master cylinder on my 73 it came with a short and long rod.... If you are using a rod that is too short you won't get the travel you are supposed to have. One other thing I found was that the 72 master cylinder provides easier pedal effort with the 73 wheel cylinders than you get with the 73 master culinder.
