Westerbeke 8.0KW-60Hz Service Manual page 61

COLISEUM GENERATOR
TO ACCESS THE ROTOR ASSEMBLY FOR
TROUBLESHOOTING
1. Remove the six (5mm) allen head screws that hold the
end cover to the generator housing.
2. At the 9:00 and 3:00 O'clock position are threaded
bosses. Thread a bolt (8mm - 1.5 x 50mm) into these two
bosses. 'This will push the end cover off the housing
exposing the rotor assembly.
When re-1nstalling: Place a small amount of petroleum
jelly on the rotor bearing "O"_ring located in the cover
boss.
Position the cover onto the bearing and thread the six
(5mm) allen head screws back in place (finger tight).
TIghten the screws in a cris-cross manner drawing the
end cover onto the bearing. When fully on, tighten the
screws securely.
NOTE:
A transient voltage supressor is connected between
the
(+) and (-)
terminals of the rotating field windings
(underneath).
~SUPRESSOR
\
\ FRONT (TOP)
VIEW
SUPRESSOR
WIRING SCHEMATIC
ROTOR TROUBLESHOOTING
(Low voltage Output)
Rotating Field Winding
1. Position the rotor as shown above with the
(+)
and (-)
connections at 12 O'Clock.
2. Place the ohm meter leads across the
(+)
and (-)
connections and record the ohm valve. Also check that
there is no continuity between either the
(+)
or the (-)
connections and the rotor shaft.
Diodes and Auxiliary Windings
1. Test the diodes on the (+) and (-) sides by lifting the
leads from the auxiliary winding studs
A, B,
and C
as
illustrated. Test each diode for an open or short.
NOTE:
The three pairs of windings should hove the same
ohm values.
2. Test the auxiliary windings in pairs. Check the ohm
values between A and B, B and C, A and C and record.
Check that there is no continuity between the rotor shaft
and windings A, B, and C ..
3. Test each diode individually. A resistance value should be
found through the diode in one direction and, with the
meter probes reversed, show no ohm value. The ohm
value found for each diode should be approximately the
same.
TEST EACH OF THE WINDING LEADS
INDIVIDUALLY AS SHOWN THEN DO
THE SAME WITH BAND C.
~
WES'7l:RBEKE
A FAULTY DIODE CAN BE
PRESSED OUT AND REPLACED
Engines
&
Generators
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