Komatsu 4D98 Series Shop Manual page 92

7. Fuel Injection System/Governor
7.3 Fuel Injection Valve
Point 7
Disassemble:
l
Check the fuel injection pressure and spray pattern. See 3.6 in Chapter 3 for tlie inspection
method.
7.4 Fuel Feed Pump
(1)
Components
L
Plug
(2) Disassembly procedure (Reverse the procedure below for assembly.)
@
Remove the feed pump assy from the fuel injection pump.
@
Remove the priming pump and check valve.
@ Remove the plug and check valve from the fuel outlet side.
@ Remove the plug, and remove the piston.
@ Remove the snap ring, and remove the tappet assy, spring and push rod.
(3) Parts inspection and measurement
(3.1) Check valve
Replace with a new one as a rule.
Check mainly for deformation and partially
wear.
(3.2) Piston
Check mainly for surface defect and wear.
(3.3) Springs (piston and check valve)
Check mainly for surface defect, fatigue
and rust.
Check valve
Piston
7-7