This instruction show you guide on how to remove and install fuel supply pump for Komatus PC130-8 excavator.For more Komatsu case,please refer to:Komatsu trouble repair.
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Caution:Disconnect the cable from the negative (–) terminal of the battery.
Open fuel drain valve (1) and drain the fuel.
Open the fuel tank cap in advance.
Fuel tank: 247
Open and lock engine hood
Remove bracket (3).
Disconnect connector PREG (4).
Disconnect wiring clamps (5), (6) and (7).
Disconnect fuel hose (8) from the supply pump.
Remove 2 boots (9) from the common rail and supply pump.
Loosen sleeve nuts (10) and (11) and remove high-pressure pipe (12).
Remove the pin and disconnect spill hose (13).
Remove joint bolts (14), (15) and (16) and fuel tubes (17) and (18).
Joint bolt (16) is fixing fuel tube (18) to under supply pump (25).
Removal of supply pump and pump holder assembly
1) Remove 4 mounting bolts (19) from the gear case side.
2) Fully loosen mounting bolts (20) on the pump holder side. [*4]
Mounting bolts (20) cannot be removed from between the supply pump and pump holder at this time.
3) Remove supply pump and pump holder assembly (21).
The following figure shows locations (a) of mounting bolts (19).
Remove the supply pump assembly from the pump holder according to the following procedure.
1) Loosen nut (22) and pull out supply pump gear (23) with gear puller 
Fully loosen the nut and keep it installed to the shaft until the supply pump gear is pulled out.
Remove 3 nuts (24) and remove supply pump (25) from pump holder (26).
The following figure shows locations (b) of mounting bolts (24).
Carry out the installation in the reverse order of removal.
Set the boot slit facing outward and downward.
The boot is designed with fire safety to prevent fuel from splashing onto the hot engine if fuel leaks.
Never bend a high-pressure pipe for the convenience sake.
The clamp used for fixing a high-pressure pipe must be a genuine Komatsu part and it must be tightened to the specified torque.
Be sure to install the boot to the sleeve nut after installing the high-pressure pipe.
Before installing a high-pressure pipe, confirm the following points. If any abnormality was found, replace it with new one. Otherwise, leakage of fuel can result.
No visible striations (b) or patchy dents (c) in the taper seal portion of the connection (a) portion: area 2 mm inside the tip).
No deformation in portion (d) (at the end of the taper seal portion: 2 mm inside the tip).