Packard Forum Index » V-8 (1955-56)

I got a rebuilt Bendix Treadle power brake unit from Kanter and about to install it. my question is about how to connect to vacuum system. There are two vacuum ports on the unit. When I removed the old one, one had a short rubber hose that was sealed with a bolt and a clamp. The other had a hose that tee-d into a vacuum line. The bolt line can't be correct, so are the two lines so the brake unit is in series with other vacuum connections (i.e an "in' and an "out")? Or is one of these supposed to be atmospheric and the other to vacuum system (and if so, which is which)? I've look through these forums as well as googling around and have not been able to find the answer on my own.

thank you,
Bob

The Treadlevac with two ports was only original equipment on the 52s, but that is not a problem as it will work quite OK on your Patty. As these car were serviced over the years units often got swapped around.

The extra connection is for a vent for the booster. That vent was remotely mounted on the 52s, and was built into the booster on later units. You can check which is which by just giving the pushrod a good push. The vacuum connection will expel air, and the vent will suck in. Of course the vent should not be plugged. I would hook a piece of tubing on it and bunch up a wad of cloth with a zip tie on the free end for it to breath through. They didn't plan on keeping out anything much finer than insects and gravel.

Should be a picture of the original setup in in 52 service bulletins when they introduced the power brake.

Ir sounds as if you have one of the original units that had an external breather and filter unit. I believe that one was only used in 52 and after that all the units had the breather under a rectangular cover attached directly to the upper side of the canister and only a single hose connection for the vacuum. Does this look like your unit? If so vacuum goes to the top connection and the breather and filter connection is the bottom. If your other unit was the same not sure how it could have been operating properly with the breather closed off.

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Thank you both for the great info. I guess since I sent Kanter a unit with 2 ports, they sent me one in return. I understand now how to set it up.

The car was barely braking when I bought it. THe hydraulic side was full of brake fluid turned to gel and my guess is that the vacuum side was shot as well (pedal would go almost to the floor before any braking action). So I would expect the vacuum side was pulling in outside air affecting engine performance and plugging breather side was the way to keep engine running well but ignoring braking problems .

I've only had the car a month or so and I'm still have a lot to learn. Thanks to you guys I know I'll be able to figure it out.

thx

Bob

Thanks to you guys I know I'll be able to figure it out.
I say that all the time! Glad to have you aboard.