Manitowoc Grove RT765E-2 Service And Maintenance Manual page 245

RT765E-2 SERVICE MANUAL
6. Clamp the flushing gun nozzle firmly to a hose attached
securely to the engine water outlet opening. Fill the
engine block with water, partly covering the water inlet
opening to permit complete filling.
7. Turn on compressed air to blow out water and loose
sediment. Continue filling with water and blowing out
with air until flushing stream comes out clear.
8. When the vehicle is equipped with a water heater
connected to the cooling system, flush the heater,
following the same procedure as for the radiator core.
9. After completing the flushing operation, clean out the
surge tank overflow pipe; inspect the water pump; clean
the thermostat and the radiator cap control valves.
Check the thermostat for proper operation before
installation.
10. Blow insects and dirt from the radiator core air
passages, using water, if necessary, to soften
obstructions.
Component Inspection
Radiator/Surge Tank
1. Side Tanks - Look for leaks, particularly where the tank is
attached to the core. Vibration and pulsation from
pressure can fatigue soldered seams.
2. Filler Neck - The sealing seat must be smooth and
clean. Cams on filler neck must not be bent or worn so
as to allow a loose fitting cap. Ensure the overflow tube
is not plugged.
3. Radiator Cap - This is the pressure-setting type. Its
purpose is to hold the cooling system under a slight
pressure, increasing the boiling point of the cooling
solution and preventing loss of solution due to
evaporation and overflow.
The cap has a spring-loaded valve, the seat of which is
below the overflow pipe in the filler neck. This prevents the
escape of air or liquid while the cap is in position. When the
cooling system pressure reaches a predetermined point, the
cap valve opens and will again close when the pressure falls
below the predetermined point.
When removing the pressure type cap, perform the
operation in two steps. Loosening the cap to its first notch
raises the valve from the gasket and releases the pressure
through the overflow pipe. In the first stage position of the
cap, it should be possible to depress the cap approximately
0.13 in (3 mm). The prongs on the cap can be bent to adjust
this condition. Care must be taken that the cap is not too
loose as this would prevent proper sealing.
GROVE
Loosen cap slowly and pause a moment to avoid possible
burning by hot water or steam. Continue to turn the cap to
the left until it can be removed.
4. Tubes are very small and can easily become clogged by
rust and scale. The general condition of the cooling
system and operating temperature are indications as to
whether or not tubes are clean. Another good test is to
feel the core for cold spots.
5. Fins are thin metal sheets that dissipate heat picked up
by the tubes. They should be kept free of bugs, leaves,
straw etc., so as to allow the free passage of air. Bent
fins should be straightened.
Engine Water Jacket
The water jacket permits coolant to be circulated around the
cylinder walls, combustion chamber, and valve assemblies.
Some of these coolant passages are small and can easily
become clogged, if the cooling system does not receive the
proper maintenance.
1. Core Plugs - These are sometimes mistakenly called
freeze plugs. They do not provide protection against
freezing expansion, but are only present because of
engine block casting methods. Remove and replace
core plugs that show signs of leaking or rusting through.
Use an installation tool for core plug replacement.
2. Drain Plugs - The water jacket of each engine could
have one or more drain plugs. These should receive
seasonal care and be kept free of rust and scale.
3. Gaskets - All gaskets must be in good condition to
prevent both internal and external leaks. If there are
external leaks around gaskets, there may also be
internal leaks into the engine. Proper tightening of the
head bolts with a torque wrench is essential for
preventing leaks around the head gasket.
Water Pump
The pump should be checked carefully for leaks and proper
lubrication. Replace or rebuild if leaking, cracked, or worn.
Fans and Belts
The fan should be checked for cracked or broken blades.
Refer to Engine Drive Belts, page 7-3.
Thermostat
The thermostat is of the nonadjustable type and is
incorporated in the cooling system for the purpose of
Published 9-04-2014, Control # 422-08
POWER TRAIN
CAUTION
Burn Hazard!
7
7-19