STEYR MOTORS Marine Engine 2012 Series, Service Manual

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Fuel System
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defects on an injector must be undertaken this
injectors with such symptoms needs to be
exchanged.
6. Repeat test on each unit injector
7. Assembly is done in reverse order.
ATTENTION: Absolutely make sure to
remove special tool No. VR
00148/0 from camshaft
housing.
Use new sealing
ring on plug screw.
03.14.02 Manual check of unit injector without tool No. VR 00148/0
Fuel System Check :
1. Investigate condition of return fuel. There should be neither air bubbles nor
discoloration (gray/white) in the fuel.
2. Check proper flow quantity (i.e. engine at idle - flow rate after engine block 200 to
240 l/h or approx. 50 to 62 gal./h)
Injector Check:
To feel the injection activities, move the control rack (quantity delivery) in between its
acceptable travel (5 to 14mm) while depressing the „plunger“ with the rocker arm.
For safe and easier handling, use our special tool lever (refer to picture in 03.14.01)
While moving the rocker arm (and/or the plunger up and down), try to get the control
rack into idle delivery position (approx. 4-5 mm). In this spot you will feel only a very
slight/short pressure build up as the duration of injection is very short
(~5mm³/stroke).
Keep this position on the control rack (freeze there) and then move over with tool VR
00126/0 to the next unit injector/rocker arm to repeat the plunge movement and feel
the resistance during injection.
The test should give an equal pressure load/peak on each injector, while maintaining
the same position on the control rack.
If one injector fails to show any pressure or this pressure peak is found in a much
higher position of the control rack, this is an indication for a possible deficiency on
this injector.
ATTENTION:
Before removing this unit injector from the engine, check for proper
adjustment of the linking lever and for correct fit/tightness and/or
torque of the unit injector mounting nuts.