DaimlerChrysler LH New Yorker 1994, Электронное руководство по обслуживанию

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(3) Attach one end of a 6.35 mm (.250 in.) ID clear
hose that is approximately 1219 mm (48 in.) long, to
the bleed valve in the thermostat (Fig. 3). Route the
hose away from the accessory drive belt, drive pulleys
and electric cooling fan. Place the other end of hose
into a clean container. The hose will prevent coolant
from contacting the accessory drive belt when bleed-
ing the system during the refilling operation.
(4) Open bleed valve.
(5) Slowly fill coolant pressure bottle (Fig. 2) until a
steady stream of coolant flows from hose attached to
the bleed valve.
(6) Gently squeeze upper radiator hose until all air
is removed from system.
(7) Close bleed valve and continue filling to the top
of the coolant deaeration pressure bottle (Fig. 3).
(8) Install cap on coolant pressure bottle.
(9) Remove hose from bleed valve.
TESTING SYSTEM FOR LEAKS
With engine not running, wipe the deaeration filler
neck sealing seat clean.
Attach a radiator pressure tester to the coolant
deaeration bottle, as shown in (Fig. 4) and apply 104
kPa (15 psi) pressure. If the pressure drops more
than 2 psi in 2 minutes inspect all points for external
leaks.
All hoses, radiator and heater, should be moved
while at 15 psi since some leaks occur while driving
due to engine rock, etc.
If there are no external leaks after the gauge dial
shows a drop in pressure, detach the tester. Start
engine and run the engine to normal operating tem-
perature in order to open the thermostat and allow
the coolant to expand. Re-attach the tester. If the
needle on the dial fluctuates it indicates a combustion
leak, usually a head gasket leak.
WARNING: WITH TOOL IN PLACE PRESSURE
BUILDS UP FAST. ANY EXCESSIVE AMOUNT OF
PRESSURE BUILT UP BY CONTINUOUS ENGINE
OPERATION MUST BE RELEASED TO A SAFE
PRESSURE POINT. NEVER PERMIT PRESSURE TO
EXCEED 138 KPA (20 PSI).
If the needle on the dial does not fluctuate, race the
engine a few times. If an abnormal amount of coolant
or steam is emitted from the tail pipe, it may indicate
a faulty head gasket, cracked engine block or cylinder
head.
There may be internal leaks which can be deter-
mined by removing the oil dip-stick. If water globules
appear intermixed with the oil it will indicate an
internal leak in the engine. If there is an internal
leak, the engine must be disassembled for repair.
Fig. 2 Filling Cooling System
Fig. 3 Bleeding Cooling System While Filling With
Coolant
Fig. 4 Pressure Testing Cooling System
COOLING SYSTEM 7 - 13