Packard Forum Index » Post-War (1946-54)

Hi Guys:

Almost devine intervention here! I recently adjusted my Emergency Brakes. Due to the horror stories, I've read on this board, about the Treadle Vac. Well guess what? I had one of those failures, coming home from a car show, yesterday.

On coming to a stop sign. The brake pedal went slowly to the floor. With minimal braking action. Thank god for the recently adjusted Emergency brake! On repeated pumps, I got some braking action back. But it wasn't right.

I drove slowly home, on pins and needles. With the Emergency Brake as my backup. It worked beautiful, by the way. Better, I thought, than a 2 wheel mechanical brake ever would.

On arriving home, I checked for leaks around the wheel cylinders. There appeared to be none. The fluid level, in the master cylinder appeared to be good also. So this appears to be a bonifide BTV failure.

The BTV in my Packard was rebuild professionally about 20 years ago. So that doesn't bother me. But the mode of failure does!!

I think I read, someone on this board, is doing a study on these failures. Well you can add this to that study.

Thanks for the warnings about the BTV!! I wouldn't have known this if it weren't for you guys! It possibly saved my Packard. And or someone elses life of property.

Finally; Adjust those emergency brakes!! They actually work quite good when adjusted.

Warren

Glad you made it home safe with the car! I'm sure some will say you somehow caused it to fail or it was the rebuilder 20 years ago, but i think you may have a good example of what packard treadlevac drivers fear most! Even if you get it rebuilt properly, how long will it take to get your confidence back?

Quote:

As one who had 4 (count 'em 4!) BTV failures on professionally rebuilt units, I say NEVER will you get your confidence back.

Replace the POS with a modern dual master system.

Craig

okay....well it was 20 years ago....good thing you did the E brake, but i may have actually thought...hmmm been 20 years...how much do i drive it....and can i take the time to pull it out and just check it out....i mean it has been 20 years and when was the last time i changed the brake fluid.

not trying to burn you, just saying is all. things don't last forever (even if they seem to be working fine) Preventive maintenence is sometimes the best practice.

without further investigation...one can't say it was the user or the BTV that failed....the jury is out.

eiher way i am glad you are safe and that the e brake came through for you! i'm glad the Packard is safe as well! cheers!

Hank

Quote:
"On coming to a stop sign. The brake pedal went slowly to the floor. With minimal braking action."

THis is the biggest problem with the BTV master cylinder COMPESATOR PORT design. It gives NO forwarning of any failure. The more historically popular PISTON AND CUP master cylinder design, just short of exclusively used now and for many decades, in most cases will give some reasonalble forwarning of failure.

20 years is a long time for rubber life depending on how it was treated or stored. Might be a good candidate for Fred's inspection program.

If nothing obvious, then if someone takes it apart, would be curious to know if there are little chunks of congealed brake fluid or other unknown particles floating around in the cylinder section. One of my theories has been because of the mounting angle and location of the compensator port, any chunks will float to the top and lodge under the valve so the port can't seal.

One other interesting thing is yours is a 54. I don't recall many reports of failure of the earlier compared to the V8 models.

Sure, I figured I'd get beaten up with the 20 year statement. I actually meant it as a compliment to the parts supplier and rebuilder. 20 years is great for any braking system.

My PM program for this car is actually quite good. With the brake system being flushed often. Due to it's inactivety.

That wasn't the point. The point was the mode of failure, "NO WARNING!!". And to warn you fellows, with Easamatics, to check your emergency brake.

That wasn't the point. The point was the mode of failure, "NO WARNING!!". And to warn you fellows, with Easamatics, to check your emergency brake.

Unfortunately, that is pretty much the scenario. Stop at one light and not the next. I believe Packard34s gave out on him when he was going at a good clip and needed to slow down for a turn. Doubt response time before even thinking of the emergency brake would have helped there.

I'm glad that you are safe with no damage to anyone and no damage to your car.
On my 57 Buick I had a front brake hose blow just as I was attempting to stop for a red light. No warning, no slow pedal going to the floor - just gone! That also tested my blood pressure. The point is, it came with no warning. What type of warning does anyone expect with a failure?

Conventional single-piston master cylinders (as differentiated from a BTV) generally give plenty of warning to attentive drivers. A gradual dropping of the pedal toward the toe board when you keep pressure on the pedal is the normal warning. If you keep the fluid up, you can normally drive like this for a while but need to pump the pedal once or twice before applying the brakes firmly. This did happen to one of our Henry Joy V tour participants in a 42 Clipper, and he did manage easily to complete several hundred more miles without problems and get home to take care of it there.