Westerbeke W-46 - Page 66

FUEL SYSTEM
.1. Idling and Maximum No-Load Speed Adjustments
These adjustments are initially made at the factory during engine
testing. To adjust idle. spe.ed, loosen the 8~mm locknut and ·adjust
the ptop screw (1) . clockwise to increase idle speed, or
counterclockwise to lower idle speed; normal idle speed is between
out, to lower (8 nun stop screw) normal idle speed is between
700-850 RPM.
This may vary with install-
ations and reduction gears
used. No-load speed is
adjusted and sealed at the
factory with 8-mm stop screw
(2). RPM full open throttle in
neutral is 3220 RPM. Do not
tamper with this adjustment.
(NOTE: Propeller load should
hold engine speed between
2900-3000 RPM, full open
throttle, underway,.and in for-
ward gear.
Any time RPM is questionable, ensure that tachometer calibration
is correct with engine speed before attempting·other adjustments.
2. Fuel Injection Nozzles
a. Description
The injection nozzle pro-
.vides a means of spraying
fuel, delivered under
pressure from the injection
pump, into the precombustion
chamber. The nozzle sprays
oil in a conical pattern
of finely-atomized droplets.
The mating surfaces of the
nozzle holder body, dis-
tance piece and nozzle are
precision-finished to
be oil tight.
The injection pressure is
adjusted by an adjusting
washer. Increasing the
thickness of the washer will
increase the spring tens ion
and, hence, the injection
pressure, and vice versa.
8
1
l-Retaining nut
2-Nozzle tip
3-Distance piece
4-Pressure pin
5-Spring
6-Washer
7-Nozzle holder
8-Gasket
9-Nut
Inspection Nozzle - Sectional View
1....-IWESTERBEKE
f Engines & Generators
64.
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6
4
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