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WEBM1000 Maintenance Section (D6T LGP (OEM))
ARD Spark Plug - Replace
ARD Spark Plug - Replace
Removing the Spark Plug
Personal injury can result from air pressure.
Personal injury can result without following
proper procedure. When using pressure air, wear
a protective face shield and protective clothing.
The maximum air pressure for cleaning purposes
m
ust be red
uced to 205 kPa (30 psi) when the air
nozzle is deadheaded.
NOTICE
If the engine is running or the key is in the ON
position, the ARD
plug will continue to fire. Turn the
key to the OFF position before servicing the ARD
plug.
1. Open the right engine access door.
152
Illustration 152
(1) Wiring harness
(2) ARD spark plug (aftertreatment regeneration device)
2. Remove wire harness (1) from spark plug (2).
3. Debris may have collected in the spar
k plug well.
Thoroughly remove any debris. Use compressed
air. The maximum air pressure for cleaning
purposes must be below 205 kPa (30 psi).
Ensure that the area around the spark plug is
clean and free of dirt and debris.
4. Use a
deep well socket and a breaker bar to
loosen the sp
ark plug. If necessary, see your
Caterpillar dealer for the part number of the
socket. After the spark plug has been loosened,
use the socket to remove the spark plug by hand
in order to detect problems with the threads.
After the spark plug has been removed, inspect
the used spark plug and the gasket.
If the spark plug could not be removed by hand,
clea
n the thr
eads with a 305-2389 Brush. This tool
scrapes debris from the seat and from the threads.
NOTICE
Do not use a thread tap. A thread tap will remove
metal unnece
ssarily. The threads could be stripped
and the combustion group could be damaged.
Installing the Spark Plug
Note: Do not use anti-seize compound on the spark
plug. Most of the heat is transferred through the
threads and the seat area of the spark plug. Contact
of the metal surfaces must be maintained in order to
provide the heat transfer that is required.
1. Ensur
e that the spark plug is clean and free of
dirt an
d oil.
NOTICE
Do not overtighten the spark plug. The shell can be
crac
ked and the gasket can be deformed. The metal
can deform and the gasket can be damaged. The
shell can be stretched. This will loosen the seal that
is between the shell and the insulator, allowing
combustion pressure to blow past the seal. Serious
damage to the engine can occur.
Use the proper torque.
2. Install the spark plug by hand until the spark
plug contacts the ARD. Torque the spark plug to
the proper specification. Refer to Specifications,
“Spark Plug” for the proper torque specification.
3. Co
nnect the wiring harness.
4. Close the right engine access door.
Backup Alarm - Test
The backup alarm is on the rear of the machine.
In order to test the alarm for proper functioning, turn
the engine
start switch to the ON position.
Apply the service brake. Release the parking brake.
Move the speed range
selector to the REVERSE
position.