Westerbeke 5.0KW BCG-60Hz Service Manual page 61

THE ELECTRONIC GOVERNOR
MAGNETIC PICK-UP [MPU] INSTALLATION
The MPU is installed in the threaded opening on the side
of the flywheel bellhousing. This positions the MPU over
the teeth of the flywheel ring gear.
Viewing through
this
opening, manually rotate the engine
crankshaft so as to position the flat of one of the ring
gear's teeth directly under the opening. Thread the
~U
into the opening until it gently contacts the flat of
this
tooth (Thread is 3/8" x 24). Back the MPU out of the
opening one turn and then lock it in this position with the
jam nut. This will position the end of the MPU .
approximately 0.030
inches away from the fiats of the nng
gear teeth.
To ensure the MPU is positioned correctly, slowly rotate
the crankshaft by
360
0
by hand to assure there is no
phy~ical contact between the MPU and the ring gear teeth.
If
contact is felt between the MPU and the flywheel teeth,
the MPU may be damaged. Remove the MPU and inspect
it Replace if necessary and repeat the above
installation procedure.
NOTE:
When replacing tlie Magnetic Pick-Up (MPU) it
MUST
be replaced without cutting and splicing into the
existing wiring cable. Doing so will cause a erratic A C
signal to the controller.
:=:====
O.030in
--
GOVERNOR CIRCUIT VOLTAGES
Below are the voltages normally found in the governor
circuit when the system is functioning normally. These
voltages are an approximate and should be of help in
troubleshooting a system that is
not
functioning correGtly.
DC Voltage
into
Controller
Bat
+
to Bat - (battery charging voltage 13.5 -14.5 VDC)
(Terminal block #1 and #2)
DC Voltage
to
Actuator
ACT to ACT (5.5 - 6.5 VDC)
(Terminal block #5 and #6)
AC Voltage from
MPU
into Controller
MPU to MPU (2.5 - 7.0 VAC)
(Terminal block #3 and
#4)
This voltage spread is the result of the distance the MPU is
positioned from
the
fiat of the flywheel ring gear tooth.
The closer to the tooth, the higher the
AC signal.
The
further away, the lower the AC signal.
Engines
&
Generators
53