"Jesus M. Jimenez" wrote:
> Does anybody know the best way to adjust the front brakes on the '55 Ply
> for toe and heel?
I recently got a copy of the WPC Club Bulletin from January, 1983. It
has a great article on adjusting total contact brakes. I'm going to
copy it as it is in the magazine. The comments in [brackets] are mine.
THE LOCKHEED BRAKE
A MAJOR ADJUSTMENT
By George Von Gaertner
The majority of Chrysler products utilized the Lockheed brake from the
late 20's up through 1955 [although the procedure seems to be similar
for all Total Contact brakes]. Dodge and Plymouth continued to utilize
this design in 1956 except the H.D. Dodges. Plymouth generally used a
10" diameter drum while Dodge used the 11" version. DeSoto and Chrysler
used both 11" and 12" versions depending on year and vehicle.
This particular brake design is characterized by the fact that one end
of each brake shoe is "anchored" onto a bolt. Each anchor bolt is an
eccentric bolt with an arrow pointing to the high side.
Each time the brake shoes are replaced a "major" brake adjustment should
be done which includes adjusting the anchor bolts.
A "minor" brake adjustment is done to compensate for normal lining
wear. A minor adjustment is done by simply adjusting each of the two
(2) cams on the back of each brake plate. (See diagram) [I will post
this whole article, including pictures, on the web site]. My procedure
is to spin the wheel while rotating the cam. When the brake shoe slows
the wheel I back off the cam until the wheel rotates freely. I rotate
all the wheels in a forward direction except when adjusting the rear cam
on each rear brake. For each of these cams I rotate the wheels in a
backwards direction.
A major brake adjustment can be done without special toos by the
following method:
1) Cut a slot at the threaded end of each anchor bolt [meaning from the
rear, the part of the bolt that sticks through the brake plate to the
outside] using two (2) hacksaw blades together. The slot should run
parallel to the arrow at the other end of the bolt. [I would use a
couple of small cutting discs on a Dremel tool and just grind the slot
in to the bolt. It'll be easier and make a cleaner cut].
2) Assemble brakes with anchor bolt arrows pointing away from each brake
shoe. [Replace drums and wheel]
3) Adjusting one brake shoe at a time turn the adjustment cam until the
shoe just drags.
4) Turn the anchor bolt [using a screwdriver in the slot you have
created] until the drum turns freely.
5) Again turn the adjustment cam until the shoe again just drags.
6) Again turn the anchor bolt until the drum turns freely.
7) Repeat these procedures until adjusting the anchor bolt will not free
the drum.
8) Back off both anchor and cam bolts until drum turns freely.
9) Repeat these procedures until all shoes are adjusted.
10) Tighten anchor bolt locknuts and install cotter pins where needed.
While a major brake adjustment should be done whenever brake shoes are
replaced, it should also be done if you encounter a spongy brake pedal
that cannot be eliminated by bleeding the hydraulic brake system. A
major brake adjustment may also be needed if you have excess pedal free
play even though your drums are true and you've done a minor brake
adjustment.
[END]
-Dave Stragand
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