Engine Coolant Heater (M07001); Heating Element - Komatsu 830E Shop Manual

To aid in cold weather starting, the truck can be
equipped with cooling system heaters. Two high ca-
pacity coolant heating units are mounted under the
engine on the power module subframe. The system
includes:
• Heaters
• Thermostats
• Coolant Shutoff Valves and Hoses
• 220 volt Receptacle
• Power Cables, Thermostat Wiring, and Junc-
tion Box
Heater operation is controlled by a thermostat
mounted on the intake end of the heating units. The
thermostat turns the heater ''On'' at 120°F (48°C) and
''Off'' at 140°F (60°C). Shutoff valves allow heater ele-
ment or thermostat sensor replacement without loss of
engine coolant.
Do not operate engine while the cooling system
heater is plugged in. The flow check valve elimi-
nates coolant flow through the heater while the
engine is running. This will cause a lack of circula-
tion in the heater and burn out the heating ele-
ments.
Maintenance
To check for operation of the heating units, the outlet
water hoses should feel warm to the touch.
1. Check all electrical connections to insure proper
connections are made.
2. Check for a burned out heating element. (Do not
remove heating unit from the truck.)
a. Remove the two Phillips head screws and slide
end cover out of the way.
b. Connect a voltmeter at the two electrical termi-
nals and check for operating voltage (220 to
230 volts) while coolant temperature is below
120°F (48°C). If correct voltage is present, the
heating element is defective and should be
replaced.
3. If correct voltage (measured above) is not read at
heating element terminals, the thermostat is de-
fective and should be replaced.
M07001 3/95
ENGINE COOLANT HEATER
Engine Coolant Heater

HEATING ELEMENT

Removal
1. Disconnect the external power source at the plug-
in receptacle.
2. Close the shut-off valves located at the inlet and
outlet ports.
3. Remove heating element.
a. Remove the two Phillips head screws from
cover at power cable entry. Slide cover out of
the way.
b. Disconnect the two electrical leads and remove
heating element from the cartridge.
Installation
1. Install new heating element.
a. Cover the new heating element threads with an
anti-seize thread compound.
FIGURE 7-1. COOLANT HEATER
1. Thermostat
2. Heater Assembly
3. Water Outlet Port
91464
4. Heating Element
5. Cover
6. Terminals
M7-1