Inspecting Fuel Spray Pattern Of Fuel Injection Nozzle; Cleaning And Replacing Faulty Nozzle - Mitsubishi S3Q2 Service Manual

FUEL SYSTEM
2.1.2 Inspecting fuel spray pattern of fuel injec-
tion nozzle
(1) When adjusting the nozzle opening pressure using a
nozzle tester, check for clogged nozzle hole, fuel spray
pattern, and fuel dribble from the spray hole.
(2) Checking points of fuel spray pattern are as follows:
· Fuel is injected straightly.
· Fuel is injected in a spray of fine droplets.
· Fuel is injected without after-dribbling.
(3) If the spray pattern is defective, clean or replace the
nozzle tip.
2.1.3

Cleaning and replacing faulty nozzle

When pulling out the nozzle tip, be careful not to dam-
age the tip.
(1) Loosen the retaining nut, then remove the nozzle tip,
and clean the needle valve and body.
(2) Clean the nozzle tip in clean wash oil. After cleaning,
assemble the needle valve and body in clean diesel fuel.
Note: The needle valve and body are precision parts.
Handle them carefully, and do not change the
combination of the valve and body.
(3) Tighten the nozzle tip retaining nut to the specified
torque.
(4) If the spray pattern is still faulty after cleaning and
adjusting, replace the nozzle tip.
Note: When using a new nozzle tip, remove the anti-
corrosive agent from the nozzle tip, and clean the
nozzle tip in wash oil. Then clean the tip again in the
fuel before assembly.
8-6
Defective spray pattern
Good After
Large
dribble
spray
angle
Inspecting fuel spray pattern from fuel injection nozzle
Cleaning fuel injection nozzle tip
Branched
Deflected
spray
spray
Needle valve
Body