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

I could not get at least one of the screws out a couple years ago when I tried to remove the cover on the car. Due to access and the screws being in tight, an offset will not work. I'll have to look again but I just remember one being where I could not see it or even get a screw driver on it.

My brother has both an Edsel and a '56 Lincoln Premiere with Treadlevacs and we've not experienced the problems we've known on the Packards. Also he rarely needs to top off the reservoir. On all four of my '53-56s, I need to top the reservoit off several times a year. And on the Premiere and Edsel, access to the unit is right there up high rather than on the ground and in the floorboard....what WERE they thinking!

Part of the problem of placement in a Packard was that the power brake unit was a retrofit to a body that had been in production over a year, and this was one of the earliest implementations that I know of. Yet, the angle of the top of the reservoir, relative to the centerline of the unit suggests an intent for mounting down low and on an angle. Later models that implemented the Treadle-Vac probably had their firewall designed with space requirements in mind, but the reservoir cover had to be redesigned.

Personally, I've never had that much trouble getting the power brake unit out of any of my Packards - unless the car was sitting in a field.

One trick I have for installation is to remove the brake pipe that goes from the master cylinder to the fitting on top of the frame rail for the hydraulic brake switch. I then install that pipe, but don't cinch it tight, on the output fitting on the master cylinder before I slip the unit in the floor board. I also omitted the cotter pin for the brake pedal and use a hair-pin style retainer, in its place.

Of course, it's been over a decade since I had one of these units in and out of a car, but the only thing I had to slide under the car for was to hook up the brake line that feeds the rear wheels.

On at least 2wo occasions i wanted to remove the toe board without removing the TV unit. Tied the TV unit up to something, i believe it was the steering column, with coat hanger or bungies or string or something like that.

Remove the toe board. Probably get to line fittings and reservoir screws easier.

I remeber now, i had to replace the rubber hose inside the vacuum can. Did it without removeing the unit or opening the brake lines. Only removed the toe board.

ok. So, is Packard the only car that mounted the TV unit so low?????? Is it lower that the wheel cylinders???? I think so with out looking.

If Packard is the only car that mounted the TV master cylinder lower than the wheel cylinders then the problem could be a faulty RESIDUAL Pressure valve. Fluid mite be draining back to the MC (siphoneing) and then down the seal lubricator port and thus sucking into the vacuum can.

FIRST QUESTION: Is Packard the only car that had the TV unit set so low????? BELOW the wheel cylinder level????

Can't answer your question about location vs. the wheel cylinders, but it would take a pretty good-sized leak at a wheel cylinder to permit that, at which point you'd have no brakes anyway. If the system is tight, it wouldn't make any difference where the MC was. Fortunate or not, I've not experienced any TV issues thru many miles on 2 different Packards.

Not leaky wheel cylinder but rather a leaking Residule Pressure valve in the master Cylinder.

Don't quite understand your logic in thinking the residual valve would be faulty and causing a problem. Also not sure that it is lower without measuring. There would have to be an air leak at the wheel cylinder as well as between the chambers in the booster for anything to siphon back. Even with a normal valve, would think the vacuum would draw under those conditions.

Why is it that NO manufacturer, including Ford used the BTV after 1959???

Might it be that there was a problem with it?

Craig

Not sticking up for them or condemning outright either but I'm wondering if the technology hadn't advanced to the point the TV was no longer state of the art & just couldn't be redesigned and keep the same package.

Maybe more HP needed more pressure & larger displacement or a dual vacuum piston which just left the TV behind. It might have been cheaper too for the mfgs to use something built in their captive supply houses instead of buying someone elses.