Komatsu H75051 Operation & Maintenance Manual page 370

MAINTENANCE PROCEDURE
3.
Turn filter cartridge (2) counterclockwise by using the filter
wrench, and remove it.
4.
Clean the filter head.
Replace inner seal (3) with a new one.
5.
Thinly apply oil to the packing surface of the new filter cartridge, then install the filter cartridge to the filter
head.
NOTICE
• Do not fill the new filter cartridge with fuel.
• Remove cap (A) at center and install the filter car-
tridge.
6.
When installing the cartridge, tighten it until the packing
surface contacts the sealing surface of the filter head, then
tighten it 3/4 turn.
REMARK
If the filter cartridge is fastened too much, the packing will
be damaged and this leads to leakage of fuel. If the filter
cartridge is too loose, fuel will also leak from the packing
clearance. Be sure to observe the tightening angle.
When tightening with a filter wrench, be extremely careful
not to dent or damage the filter.
7.
After completing the replacement of filter cartridge (2), bleed air from the circuit.
Bleed the air as follows:
1)
Fill up the fuel tank with fuel (to the level where the
float is at the highest position).
2)
Loosen the knob of feed pump (4), pull it out, then
pump it in and out until the movement becomes
heavy.
REMARK
It is not necessary to remove the plugs at the fuel prefilter
head and at the fuel main filter head.
When the engine runs out of fuel, use the same procedure
to operate feed pump (4) and bleed the air.
8.
Push in and tighten the knob of feed pump (4).
9.
After replacing the filter cartridge, start the engine and run it at low idle for 10 minutes.
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MAINTENANCE