Page 111 - Car South Africa (February 2020)

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orking on modern cars is usually a relation to the hub and bolt or stud holes.
job for experts. You often can’t even Place this over the shoes to see if they are
W get close to the snags you need to sitting too high or low, preventing the drum
investigate. One exception is the braking sys- 01 from tting snugly. Just tap the shoes into a
tem of an everyday runabout. Like the old l more suitable position and you should nd the
sics which are much simpler in design an problem will ease.
themselves to home tinkering, modern city We loosened the shoe adjusters for the Dat-
cars still use drum braking for the rear whe sun; in the Fiat’s case, automatic shoe-wear
These seldom require much attention and ar djusters using spring-loaded friction washers
therefore left alone for many years (even dec- an merely be tapped inwards. Another item
ades). Due to weight transfer to the front unde u will need to check is the handbrake actu-
braking, rear braking has a much lighter duty. r. This must be fully released and the push-
Still, they should always be in good nick. must t into its correct shoe slots. You may
to loosen the cable as it may have been
THE PROBLEM ned over time as the shoes wear.
Two brake failures recently occurred simultane-
ously to two elderly compact classics under my MORE PROBLEMS
care.These hail from the 1970s: one Japanese Once we had completed the shoe replacement,
and one Italian, both with a disc/drum braking it was time to bleed the brakes. Only one of
setup.The Fiat has a vacuum booster but the hem failed to respond to pumping of the
older-design Datsun tries unsuccessfully to do dal. On further inspection, it was obvious
without this “modern” contraption. Symptoms exible brake hose was blocked. This is
02
were intermittent locking of the rear wheel uncommon and is fairly easily recti ed by
which would later release. Fortunately, one removing both pipes and having them
case allowed a slow drive home while the emanufactured at a hydraulics special-
other manifested itself while reversing in ist. There is no point saving a few rand
the driveway.With the nearest trolley jack by replacing only the blocked one. Removal
in place, removal of the wheels soon revealed should be simple but look carefully at what is
the problem. holding the assembly together. Age, rust and
mud can hide problems. We tried to undo a
OLD AGE union before noticing a pipe could be removed

Even the most basic and robust mechanical by retracting a locating clip with pliers.
items will eventually fail. This time it was a
dual case of brake linings pulling away from NITTY GRITTY CAUTION
the steel shoes. These cars are both more than Once the wheel, drum, springs, retaining clips Be extra careful when working with brake
45 years old yet each has under 100 000 km and shoes have been removed, you will need uid. Always wash your hands after contact
on the clock, so it is possible these shoes have to visit that brake specialist for the linings and and do not allow a single drop of uid to
never been replaced. No wonder they called then replace everything in reverse. Now that touch any painted bodywork. It eats away at
it quits. Some old cars’ linings were riveted to you have much thicker linings, it can be tricky paintwork worse than paint stripper.
the shoes but nowadays the glue is so strong to replace the drums. The rst step is to push
a quick bonding is all that is needed, using the pistons in as far as they will go. It helps to
the original shoes. This makes the relining of loosen the bleed nipple to encourage this. If 01 Cardboard template for concentricity check. 02 Newly
made pipes alongside the old ones. 03 These linings fell
brake shoes a quick and relatively inexpensive you still can’t t the drum, make a cardboard
off from old age. 04 A locating clip holds the pipe in place.
job at any specialist workshop. template of the drum’s inner diameter in 05 Obvious brake-fluid leak from the slave cylinder.

03 04 05

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