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 1.
Worn front axle eyes
Austin 7 front axle kingpin eyes, when worn in the axle, can only
be safely repaired by the insertion of oversize pins. Kingpins
of 5,10 or15 thou. oversize can easily be made from a high grade
steel and ground to suit the amount of wear which is to be taken
up. They should not be hardened as this makes them brittle and
liable to break.
The advantage of this repair is that the existing bushes in the
stub axles can be used without removal and simply reamed out to
suit a sliding fit. The axle eye should be reamed to a tight fit
with the retaining cotter pin in place.
When refitting the stub axle it is important to ensure that the
hardened steel thrust washer is fitted at the bottom and any clearance
taken up by a shim washer above the axle eye. The thrust washer
should be well greased as this can cause steering wander if assembled
dry.
 2.
Understeer
"Austin 7 front axle shackle pins should be immobilised on
one side". This myth persists after the first works "Duck"
racers fitted with underslung springs and an "H" section
beam above became quite unstable in crosswinds and one shackle
had to be locked to keep them on course. This problem does not
occur on the standard chassis if all the pins and bushes are in
good condition.
 3.
It has become quite common for Austin 7's to be fitted with front
axle beams
where the radius arms are located to the chassis side rails in
place of the central ball joint under the gearbox on the front
cross member (as was the case with the early "Duck"
racer chassis). Unless the axle beam is constructed with an articulated
joint the car will suffer from terminal understeer. This is because
in order for the car to roll the axle beam would have to be twisted
like a massive anti-roll bar. Contrary to popular belief Austin
7's understeer under normal conditions and any additional roll
stiffness simply makes the situation worse. The above mentioned
"Duck" racers were modified to have tubular articulated
front axle beams which increased their speed through corners by
20 MPH (Harrison-Austin Racing History).
 4.
Shock absorbers
Shock absorbers must have their Beech wood discs boiled in tallow
to give progressive damping and avoid any hysteresis effect which
if present increases the spring rate and thereby the roll stiffness
and thus the understeer on the front or oversteer on the rear.
Note: this is not the best method of inducing oversteer.
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 5.
Brakes
Contrary to Georgano (The Complete Encyclopaedia of Motorcars)
Austin 7 brakes on the pre 1930 models had the front brakes operated
by the handlever and the rears by the foot pedal. Proprietary
conversions to couple the two systems were available at the time.
The main problem with the Austin 7 brakes, up to the introduction
of the semi-Girling system in late 1936, was that the cross shaft
on the chassis was linked to the foot pedal on the drivers side.
By the time the load had been applied to the nearside the shaft
had twisted by about 10 degrees so that the nearside rear brake
was not effective (by degrees depending on how hard the pedal
was pressed). The solution was to drive the cross shaft by means
of a tube which was outside it and pegged in (or near) the centre
so that the same degree of twist applied the same pressure to
both rear brakes. Fitting this later type cross shaft arrangement
to an early chassis makes a significant improvement to the rear
brakes of early cars.
 6.
The front brake compensation was supposed to work by the cable
sliding over the half moon aluminium casting hanging below the
centre of the cross shaft. In practice this does not work because
the angle is too acute and the cable sets in one position. A better
solution is to fit a bell crank in it's place with an adjustable
cable attached at each end.
 7.
The very early 6 inch braked axles were originally designed to
have cast iron shoes operating directly onto the pressed steel
drums. A study of the heavy shoe design confirms this theory.
These rather like the cast iron clutch linings on the "Ulster"
and racing models would have given much better braking. At some
point pre-production a decision must have been made to fit Ferodo
composition brake linings, probably to reduce running costs.
 8.
Springs
The rear springs on an Austin 7 are not bolted to the chassis
side rails but to the rear cross member. This in turn is riveted
to the chassis side rails several inches in front of the spring
"U" bolts. This allows the whole rear cross member and
chassis to flex which makes the rear shock absorbers virtually
inoperative. The solution is to extend the lower chassis flange,
to which the springs are bolted, by welding a suitable piece of
steel to level with the rear end of the side rails and then bolting
through into each side of the "top hat" section.
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