Packard Forum Index » V-8 (1955-56)

Seems my brakes are failing. I tried driving my car and the farther one travels through brakes are on . When I stopped the fronts were smoking so it clearly has a serious problem. The pedal normally seems hard but gets harder as the car travel. There has been many posts about brakes and I'm thinking the master is bad. If it needs a rebuild who are the go to vendors? I've read that some of the places that people have used have not produced reliable results

Personally, if I were going to have a unit rebuilt the first choice would be to check with Ross Miller at Speedwell Garage in Parkton, MD and see if he could fit it in. He has done several very well received rebuilds for members of the forum and is very thorough in checking everything out -- including a check of the vacuum section which some rebuilders seem to more or less ignore.

Another good option would be to get an already rebuilt exchange unit from Kanter. Max probably has them too although I don't know if they do their own rebuilds. I would not waste time with any of the multi make mass market rebuild places that advertise their services. Those are the places most seem to complain about.

Good advice on rebuilding and it's really not difficult to even do it yourself. I've done so many times and all are still on the road and working well. First, though, check to be sure that the hoses haven't collapsed internally as that would also give the symptoms you described.

Thanks for you thoughts on this issue, the hoses your mentioning specifically where are they? Internal to the master or else where?

At the front, they connect from the chassis to the cylinder in each wheel. At the rear there is a single one that connects from the chassis to the rear axle. Nearly every car ever built with hydraulic brakes has this, or a similar, configuration.

When these hoses get old, especially when the system hasn't been maintained by annual flushing and new fluid, they start to collapse internally. In their early stages of deterioration the master provides enough pressure to actuate the brakes but the brake shoe return springs might not be able to push the fluid back out into the master reservoir, causing the brakes to drag. The more the hoses collapse (and it's completely invisible from the outside), the worse the problem. This happened on our 1972 Mercedes and with one removed I couldn't even get 120lbs of air through it! It was totally collapsed shut while on storage.

The inner lining of a hose could definitely have collapsed and is preventing the fluid from returning thus keeping the brake applied on that wheel. In any case, if the hoses are old a replacement of hoses is a good idea -- even if they are not causing the problem. Hoses do have a finite lifespan and if yours are original could well be an issue now or fail suddenly down the road a bit.

If hoses and wheel cylinders are proven OK, make sure the pedal is returning all the way -- even if you have to reach down with the other foot and get under the pedal to pull it back after being pressed.

There could be something that the spring cannot overcome such as a mechanical bind with the pedal or carpet or some problem inside the air side of the treadlevac enclosure with bunched up padding or in the vacuum portion with a sticking piston caused by fluid contaminated lube. Also a vacuum leak from a problem with the control valve could be keeping the piston partially applied. Any of those will prevent the master cylinder ram from returning all the way back to the relaxed or home position. If that happens and the ram is not fully back there is a port that will not be opened and with the port not being open means fluid is trapped in the master. Temperature causing the trapped fluid in the master to expand can be as effective in applying the brakes as the pedal being pushed.

OK thanks for the clarification, the entire system was rebuilt 2 years ago so it sounds like we are talking the hoses at each wheel, I believe those were replaced at each wheel and the wheel cylinders were rebuilt.The vacuum lines I'm not sure about thanks for your insights!