Onan MDKBH Series, Руководство по обслуживанию

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8-4
SERVICING BRUSHES AND SLIP RINGS
WARNING
Accidental or remote starting can
cause severe personal injury or death. Before
removing a panel or access door, disconnect
the negative (–) cable at the battery to prevent
the engine from starting.
Brush Block
Access: For access to the brush block, remove the
enclosure front / left side assembly (Page 5-1) or
swing it out to the left. Move the second resonator
chamber (Page 8-4) out of the way by removing
the bolt that secures it to the generator and by loos-
ening the clamp at the intake manifold.
Service: Disconnect the field leads from the brush
block (Figure 8-2), remove the mounting screw and
withdraw the brush block from the generator end
bell. Replace the brush block assembly if either
brush is shorter than 7/16 inch (11 mm), binds in the
brush block or is damaged in any way.
Reconnect the field leads,
F– (black) to the outside
terminal, and F+ (red) to the inside terminal.
Slip Rings
Remove the brush block and inspect the slip rings
for grooves, pits, or other damage. Use a Scotch
Brite pad or commutator stone to remove light wear
or corrosion.
TESTING FIELD FLASH
Field flash can be tested by measuring output volt-
age while cranking with the governor actuator leads
(Page 6-7) disconnected to keep the engine from
starting. If output voltage increases at least 1 volt
while cranking, the whole field excitation system—
controller, brushes, slip rings and rotor—are prob-
ably in working order and the problem lies else-
where. See Troubleshooting (Section 11).
F–
F+
FIGURE 8-2. BRUSH BLOCK
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