Systems and scheduled
maintenance
Solé, S.A. C-243 b, km 2 · 08760 Martorell (Barcelona) ·Tel. +34 93 775 14 00 · www.solediesel.com · [email protected]
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Marine diesel engines. Operator’s manual
Maintenance task. Injector inspection
To check the injection pressure of injectors (opening
pressure) you have to follow these steps:
1.
Remove nozzle and washer.
2.
Install the injection nozzle on the tester. Slowly operate the
tester handle full strokes to bleed (remove) air from the
pipe and nozzle.
3.
Make a slow increase in pressure by operating the tester handle
at a speed of more than one stroke per second while observing
the pressure gauge.
4.
The pressure gauge reading will slowly increase and, when the
nozzle starts discharging fuel, it will go down fast. Take the gauge
reading right then as the injection pressure.
Injection pressure 13,73 MPa (140 kgf/cm
2
)
5.
To adjust the injection pressure, increase or decrease the amount of shims fitted to the nozzle
holder.
6.
Look at the orifice discharge pattern (shape of discharge) when fluid begins to flow through
the injection nozzle. The discharge must be finely and uniformly atomized. Any change is an
indication of a bad nozzle.
7.
If the nozzle is bad, remove the tip from the nozzle and wash needle valve and body in clean
washing solution.
And if the nozzle is still bad after the tip has been washed, replace the tip.
When installing the new tip, remove synthetic resin film from the tip and slide the needle valve
in the body in clean diesel fuel to wash off inhibitor completely.
8.
The washer shown on point 1 must be replaced.
When testing the injection nozzle, keep its tip pointed away from the operator. Fuel from the
orifices in the tip of the nozzle is under high pressure and can cause injury to the operator.
Maintenance task. Bleeding air from the fuel system
Prime the fuel system to bleed the air from the circuit. Trapped air in the fuel system can
cause difficult starting and erratic engine operation. It is necessary to prime the system:
✓
Before starting the engine for the first time.
✓
After running out of fuel and adding fuel to the tank.
✓
After fuel system maintenance such as changing the fuel filter, draining the fuel/water
separator, or replacing a fuel system component.
For this operation you have to follow these steps
:
1.
Loosen all the injection pipes.
2.
Start the engine to drive out air in the injection pipes and nozzles automatically.
3.
When fuel overflows from an injection pipe, tighten it up and wait until fuel overflows from
another one. Repeat it until all injection pipes are tightened.
4.
After bleeding, clean up fuel spillage.
When fuel overflows from the injection pipes, wipe thoroughly with a cloth. Spilled fuel is a fire
hazard.
