Komatsu WA250PT-5H, Operation & Maintenance Manual

Page: 222 / 255

Service procedure
MAINTENANCE
Every 500 hours service
4-48
Replace fuel filter cartridge 0.
WARNING
Engine is at high temperature immediately after the machine has been operated. Wait for engine to
cool down before replacing the filter.
Do not bring fire or sparks near the fuel.
REMARK
If the machine has run out of fuel, use Steps 3 to 10 to bleed the air.
Container to catch the oil
Filter wrench
1. Open the engine side cover on the right side of the chassis.
2. Set the container to catch the fuel under the filter cartridge.
3. Using a filter wrench, turn filter cartridge (1) counterclock-
wise to remove it.
4. Clean the filter holder, fill a new filter cartridge with clean
fuel, coat the packing surface with engine oil, then install it
to the filter holder.
Add fuel from small hole (A) (dirty side) at eight places. Do
not add fuel from hole (B) (clean side) at the center.
NOTICE
If the filter cartridge is tightened excessively, the packing
will be damaged and fuel will leak. If the filter cartridge is
too loose, fuel will also leak from the packing, so always
tighten to the correct amount.
5. When installing, screw in cartridge until seal comes in con-
tact with sealing surface, then tighten approx. an additional
1/2 turn.
6. Add fuel to the fuel tank until full (to FULL mark on the fuel
gauge).
7. Loosen air bleed plug (2).
8. Loosen the knob of feed pump (3), then pump it up and down until no more bubbles come out with the fuel from
air bleed plug (2).
9. After bleeding the air, tighten air bleed plug (2), then push in the knob of priming pump (3) and tighten it.
Tightening torque for air bleed plug: 7.8 to 11.8 N·m (0.8 to 1.2 kgf·m, 5.8 to 8.7 lbft)
10.After bleeding the air, start the engine and check that there is no fuel leakage from the filter seal surface. If
there is any leakage, check the tightening of the filter cartridge. If there is still leakage, follow Step 2 and 3 to
remove the filter cartridge, then check the packing surface for damage or foreign material. If any damage or for-
eign material is found in the packing, replace the cartridge with a new part, then repeat Steps 4 - 7 to install the
filter cartridge.