53 Power Brakes

[Guest 53 Roady]

The new Bugle has great stuff on 54s. Thanks to several of you Forum contributors. There is an interesting article on an electric vacuum pump to sustain the brakes if the engine dies. I tried to buy rebuild parts for our 53 and was told the power master cylinders were recalled and modified and that I could have ours sleeved and updated or I could try to find a 55. I cleaned up all of the parts in our 53 and put it back together. The bore looked good and the cups may have been new in 1990. I replaced all wheel cylinders and hoses and switched to dot 5 fluid. I have good brakes. I would guess that the 53 has any problems that 54s do and perhaps more. I have the engine running reliably now but before I got the fuel system clean it would die and the car was a bear to stop. Any advice or comments.

Pat

[trp3141592]

Hi,

There have been many threads concerning the Hayes power brake set-up on 53's. In a word--they are/were dangerous. A search of the forum will lead you to many articles.

--Tom

[MrEarl]

Pat, hopefully your power brake unit was exchanged during a late 53/early 54 year campaign (not a recall mind ya) that was held to correct a major problem of a bad o-ring within the power cylinder assembly. Or if not then then hopefully at some point afterward. This o-ring if failed would allow brake fluid to bypass, get sucked up into the engine manifold and out the exhaust pipe. All this unbeknownst to the driver until he tried to stop the 2 ton monster. If it was replaced and if your car is original, there may be a white X painted on the cowl to indicate the brake cylinder was replaced. The new part number for this unit was 116302. One little o-ring caused quite a stir back in 1953-54. (as did another 0-ring failure in the space shuttle Challenger in 1986) Ralph Nader blasted GM for the '53 Buick power brakes in Unsafe at Any Speed. http://www.american-buddha.com/nader.unsafeanyspeed.2.htm

It was probably the deaths, damages and lawsuits brought about by failures caused by that little o-ring that prompted Buick to realize the problem with the 53 brakes also not having a back up air supply to the power brake cylinder if the engine died. This was "corrected" in '54 by installing a small air pump that would, upon loss of engine vacuum, come on and supply sufficient air to operate the power brake cylinder. The problem with that was the vacuum pump motors would burn out or the relays that activated the pump failed. Not until 1955 did some bright Buick engineer figure out that you could store sufficient compressed air in a fruit juice can to provide this needed vacuum and so redesigned the 55 brakes to incorporate a vacuum reserve tank 9looking much like a fruit juice can to me) with a check valve that closed when the manifold vacuum fell below that of the brake system.

I would suggest to you that you at least upgrade your system by at minimum installing a '54 vacuum pump with relay. These units, especially the relays are hard to find these days and generally run around $3-400 when you do.

Edited June 9, 2014 by MrEarl (see edit history)

[MrEarl]

Tom, I noticed in your signature you have a 1949 Achinback. I recently acquired a 1950 Achinknee and was wondering if you might be interested in it. I could cut you a great deal on it.

[trp3141592]

Mr Earl,

I have expanded my pain collection to include two Achinknees. There is no quantity discount benefit. Thanks for the offer.

--Tom

[buick5563]

I have a later model (Circa 1967) Achinback. Not a whole lot changed in design.

[Guest 53 Roady]

Thanks guys. By the way Mr. Earl, Your house and yard look as good as your car in the Bugle Do you consider the house Gothic?

Pat

Edited June 11, 2014 by 53 Roady (see edit history)

[bhambulldog]

Race cars with high lift cams have a tough time producing vacuum.

Here's one of their solutions;

http://www.jegs.com/i/Stainless-Steel-Brakes/884/28146/10002/-1?parentProductId=

[MrEarl]

Thanks guys. By the way Mr. Earl, Your house and yard look as good as your car in the Bugle Do you consider the house Gothic?

Pat

Gothic? No I don't think so. Although all the neighborhood kids think it looks haunted. I think it is more of a Victorian Farm House. Thanks for the nice words Pat.

[Ben Bruce aka First Born]

Gothic? No I don't think so. Although all the neighborhood kids think it looks haunted. I think it is more of a Victorian Farm House. Thanks for the nice words Pat.

And pictures do not do it justice!!

Ben

[trp3141592]

Hi,

To "Pontiac1953" in re your inquiry

The power brake unit referred to here is the Kelsey-Hayes unit. As you can read above, it has a fatal (literally) design flaw. Many links ca be found HERE:

https://www.google.com/search?q=53+buick+power+brakes+site:forums.aaca.org&client=opera&hs=rX4&channel=suggest&gws_rd=ssl

--Tom