Air Pressure - Volvo 121 Servicing

SERVICING
Wheels and tyres
35

Air pressure

Make a habit of checking the air
pressure in the tyres regularly. The
best way to do this is to check the
pressures every time you fill the fuel
tank. See page 58 for the correct
air pressures. Do not forget the
spare wheel when you check the air
pressure. Even if this wheel is not
used, the air pressure can go down
and you may find that the tyre is
flat just when you need it.
During driving the temperature of
the tyre rises and that also of the
air pressure in relation to the ve-
hicle's speed and load. Normally
the air pressure should only be
checked when the tyres are cold. If
the tyres are warm, any alteration
should be only made in those cases
when the tyres must be pumped
with air.
165 S15
Size
speeds up to
m.p.h.).
For prolonged driving at speeds
140
above km.p.h. (90 m.p.h.) the
air pressure in the tyres should be
i ncreased by 0.3 kg/cm2
sq.in.). The pressure must not exceed
2.1 kg /cm2 (30 lb./sq.in.).
If inspection of the tyres shows that
there are particularly worn spots
and unusual wear on the tread, take
the vehicle to a Volvo workshop
for the wheels to be balanced.
4 6
tyres are intended for
175
km.p.h. (110
(4.5 lb/
Excessively low air pressure is one
of the most usual reasons for wear.
If pressure is too low, the outer
edges of the tread take the whole
loading and wear down very quick-
ly. Insufficiently inflated tyres also
result in difficult steering and high
fuel consumption.
Excessively high air pressure means
tyre wear along the centre of the
tread.