Packard Forum Index » V-8 (1955-56)

just reading post by WauhopM i was out in my 55 clipper constellation at the weekend and a similar problem occured my brakes were working fine then all of a sudden the brake pedal was going further to the floor, my brakes were still working but after pressing the pedal 4 or 5 times it was flat down, if i lifted the pedal back up i had brakes again so had to keep repeating this prosess ( and using the hand brake) to get home. living in scotland means i dont have anywhere local to service it. i see i can get a rebuild kit but not sure what to do about this as most people on the forum recomend sending them to a specialist. i have not taken the master cylinder off as yet i just checked to see if it was still full of fluid ( whitch it is ) packardV8 suggested cleaning the compensator valve ! is this something you can do with the unit in place ? or will the whole thing have to come out. thanks Jamie

That you had to lift the pedal back up suggests your unit has several issues that require attention. I'm not a fan of do-it-yourself repairs on these units so my suggestion would be to either have your rebuilt but one of the reputable rebuilders, or get a rebuilt unit on an exchange basis from Kanters Auto Parts or Max Merrit.

By the way I recieved my unit back from white post and the car is stopping fine now-I had it back within a week.

WauhopeM, you are describing the very same symptoms I experienced in my 56 400 some while back...

The problem didn't get worse but was already booked in to a local mechanic for attention. Too dangerous if a novice were to drive (if ever!)

Then one August day...
I was parked in my inclined gravel driveway with my foot on the brake pedal and hadn't noticed it had gone to the floor.

Couple that with a number of other circumstances with the car on that driveway - Pushbutton shift in Park, handbrake off and a whisper quiet engine that had stalled (unbeknown to me)

Selected Rev, foot on accelerator pedal to go back. NO WAY!
Car took off FWD for the closed garage door!

Fortunately the garage stopped the car with fender, grill, bumper and boob damage. The boob behind the wheel was not physically injured, just emotionally scarred (I get the shakes at the mere mention of BTV).

My father had a 56 Clipper which was our family car and I imported a 56 400 to Australia. Dad never reported poor pedal, but had experienced chronic brake fade.

My 400 now has a Willwood Disc conversion and an ABS Master and Booster. My beautiful car is largely back together and on the road again full time in a matter of a week (s???). Will supply specs of Master and Booster once confident with road performance.

Cheers
Russ

Regular maintenance is needed on all systems of any car, especially safety related items. Cars that are 50+ years old and not used regularly should get even more attention. Manual brake systems need attention just like power brake systems and at the first sign of trouble diagnosis and repair are in order.

I recently purchased a very nice '56 400 with power brakes from a long time Packard owner. Upon purchase I went through the entire brake system and ended up installing our Bendix Treadle Vac repair kit, wheel cylinder and hardware. It was a simple, straightforward job and I followed the directions that were supplied with the BTV kit. I also found the instructions that one of the members here up loaded very helpful.

https://packardinfo.com/xoops/html/modules/article/view.article.php?c8/404

In my case I had multiple issues with my BTV as the car had been sitting 10 plus years. The vacuum section had much fluid in it due to a leaking seal (which did create some light pitting in the canister). The lack of use and maintenance coupled with brakes fluids inherit property to absorbed water wreaked havoc on the BTV. While in there is replace the piston as well and went through and disassembled the vacuum diaphragm assembly cleaning all the various parts.

In my opinion the rebuilding was very enjoyable and rewarding at the same time. All turned out fine in fact I had a friend take my 400 for drive and he was impressed with how powerful and sensitive the brakes were, just like reports said when the car was new.

I have worked on older and newer cars in shop for years and have found that cars that are 10-15 years old do not usually need the master cylinders rebuilt/replaced, over that it is quite common. I had a similar issue a few weekends back at a shop I work at on Saturday's. It was a lower mileage 93 Cadillac Deville. One of my techs was pulling the car into the shop went to hit the brakes and they went to the floor and the car coasted out the other side of the shop (Note this shop is not part of Kanter) thank god the other garage door was open. The car had a catastrophic master cylinder failure. So it didn't matter at that point if it had a tandem master cylinder or not. What it comes down to is annual maintenance, inspection of your vehicle and how familiar you are with your car and how its systems work. Especially vehicles that will sit for long periods of time, as most of our cars due over the winter.

Brake fade is not directly related to the BTV/master cylinder. It normally is related to the lining composition of the shoes, over adjustment of the shoes or contact surface of the drum being glazed.

Thanks
James

Which is all the more reason to convert to a modern sealed power/ master cylinder unit.

Hi James, nice to persevere with original and I am happy to stick with what I have done to remove BTV failure risk.

Agree about the unrelated BTV / chronic brake fade. Context was also eliminate the brake fade risk too. The Willwood disc conversion setup bolted on very easily and cleanly - very nice piece of engineering.

Cheers
Russ

Hi all, IThis is part of the "FOR" arguement. It really is a matter of what you are confident in. My 56 Patrician has a BTV installed. I have modified the BTV breather into a filler tube and reservoir, which is mounted on the firewall. I notice that it goes down occasionally and I top it up. IMHO, the main problem with the BTV is the difficulty with checking fluid level as the system ages and master and slave leaks develop. There is also a refill problem with the BTV reservoir location. I have had no problems since installing the firewall reservoir/filler and am very happy to stay with the BTV. PT

This might be a good tread to ask about ,manual brakes on a '55. As anyone found a way to fit a modern power booster under the floor? I am currently exploring options for a tandem master down there.
Thanks.

You could probably fit a universal power system under the floor but it would have to be a small one. The frame depth is about 6" give or take so not quite as deep as a small 7" vacuum booster portion. You might have to consider hydro or electro boost systems if you don't want something hanging down. If you have torsion bars, they present another clearance issue.

The bigger problem is pedals. I don't believe any of the stock Packard linkages would work a power setup without significant mods. The BTV suspended pedal is a no go but If you have manual now then possibly the connection point could be reworked to change the ratio. Could you get the works in the same space as the current master to use the linkage lineup is a question. You might have to consider some kind of universal pedal.

If you have manual now and just want a dual master cylinder, that should be doable with several different cylinders. Revise and add some plumbing, a different mount or change holes on the frame rail, and a remote fill or a larger floor fill opening.