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4 DLT ENGINE
Pressure valve opening
pressure 0.9
+ 0.15
kg/cm
2
(gauge)
Vacuum valve opening
pressure < 0.05 kg/cm
2
Max
Checking cap
(Refer Figure 66)
C
heck radiator cap for perfect sealing in filler neck.
C
heck radiator cap, main and vacuum valve opening
pressures.
R
eplace defective cap with new one of recommended
rating.
Test for main valve opening pressure.
T
he radiator cap shall be tightened after filling in with
water. The water inside the radiator is pressurised.
Check that main valve opens at specified pressure
of 1.0 kg/cm
2
R
adiator cap main valve should not open below the
specified pressure value.
O
n the vehicle, the functioning of radiator cap main
valve can be checked by observing increase in
coolant level in auxiliary tank at high coolant
temperature.
Test for vacuum valve opening -
T
he radiator cap shall be tightened without water
inside the radiator and shall be connected to vacuum
pump. Check that vacuum valve opens fully at 0.05
kg/cm
2
vacuum.
O
n the vehicle, the functioning of the radiator cap
vacuum valve can be checked by observing decrease
in coolant level in an auxiliary tank when it cools down
compared to higher level at high temperature.
Fig. 66
(VACUUM VALVE)