Fuel System (In-Line Type Fuel Injection Pump) - Bleed Air; Fuel Filter - Bleed Air; Fuel Injection Pump - Bleed Air; Fuel Filter - Bleed Air (1) - Mitsubishi S4S-DT Operation & Maintenance Manual

Chapter 8 PERIODIC INSPECTION AND MAINTENANCE PROCEDURES

Fuel system (in-line type fuel injection pump) - Bleed air

When fuel overflow from the air vent plug, wipe thor-
oughly with a cloth. Spilled fuel causes fire hazard
After bleeding, lock the priming pump securely.If the
cap is not locked tightly, the priming pump can be
damaged, causing a fuel leakage that could lead to a
fire.
Tighten the priming pump before closing the air vent
plug.
Do not close all air vent plugs and cocks before lock-
ing the priming pump, as the priming pump will not
return to the original position due to internal pres-
sure.
Bleed air at fuel filters and then at the fuel injection
pump. Bleeding from upstream to downstream is
effective for this job.

Fuel filter - Bleed air

If air vent plugs, the thread portion of the bracket, or
sealing washers are damaged, replace them with
new ones.
1. Loosen the air vent plug on the fuel filter about 1.5
turns.
2. Turn the priming pump counterclockwise to unlock,
and prime the fuel filter.
3. When the fuel from the air vent plug becomes free
from air bubbles, stop priming and tighten the air
vent plug to the specified torque.

Fuel injection pump - Bleed air

1. Loosen the air vent plug on the fuel injection pump
by rotating about 1.5 turns.
2. Move the priming pump up and down. When the
fuel flow from the air vent plug becomes free of
bubbles, push and turn the priming pump clockwise
to lock.
3. Tighten the air vent plug on the fuel injection pump.
8-4
Turn counter-
Move cap up
and down
clockwise
[Lock release]
Fig. 8-5 Priming pump - Handle
Fig. 8-6 Fuel filter - Bleed air
Fig. 8-7 Fuel injection pump - Bleed air
While depressing,
turn coockwise
[Priming] [Lock]
Air vent plug
Fuel filter
Air vent
plug
Priming pump