Mitsubishi Heavy Industries SL Series Service Manual page 100

FUEL SYSTEM
2.1.2 Inspecting and adjusting fuel injection
valve opening pressure
Never touch the injection nozzle tip during nozzle
injection test.
(1) Mount the nozzle on the nozzle tester.
(2) Push down the handle at a speed of once a second and
read the pressure when injection starts. Make
adjustment if it is outside the standard.
(3) To adjust the injection start pressure, remove the set
screw on the nozzle holder, loosen the cap nut and turn
the adjusting screw with a driver.
(4) After adjustment, tighten the cap nut and set screw with
the specified torque.
(5) After tightening the set screw, check if the injection
start pressure is within the standard again.
Item Nominal
13.73 MPa
Valve opening
{140 kgf/cm²}
pressure
[1991 psi]
2.1.3 Inspecting fuel spray pattern of fuel injec-
tion nozzle
(1) When adjusting the nozzle opening pressure using the
nozzle tester, check for nozzle hole condition, and fuel
spray pattern.
(2) Checking points of fuel spray are as follows:
· Fuel is injected from all spray holes simultaneously.
· Fuel is injected conically at the specified spray angle.
· Fuel is injected in a spray of fine droplets.
· Fuel is injected without after-dribbling.
(3) If spray condition is faulty, clean or replace the nozzle
tip.
8-6
Standard
14.22 to 15.00 MPa
{145 to 153 kgf/cm²}
[2062 to 2176 psi]
(New parts value)
Inspecting fuel injection valve opening pressure
Replacing fuel injection nozzle tips
Defective spray pattern
Good After
Large
dribble
spray
angle
Inspecting fuel spray pattern from fuel injection nozzle
Nozzle tester
Nozzle tip end
Branched
Deflected
spray
spray