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021-027 Bearing, Generator
Remove
WARNING
To reduce the possibility of
property damage and
personal injury from
electrical shock, make
certain the unit is isolated
from all voltage sources.
Disconnect the batteries or air
supply line to the air starter to
prevent accidental engine
starting.
The non-drive end bracket
must be removed in order to
replace the bearing on all
frame sizes.
Remove the permanent
magnet exciter stator and
rotor. Refer to Procedure
021-030.
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Do not pry on the generator fan
to rotate the engine, the fan
blades can be easily bent and
broken. The entire generator
rotor must be disassembled to
replace the generator fan if
damaged.
WARNING
To reduce the possibility of
property damage and
personal injury from
electrical shock, make
certain the unit is isolated
from all voltage sources.
Disconnect exciter leads X and
XX as well as P2, P3 and P4 at
the auxiliary terminal block.
Bring the leads back into the
non-drive end bracket.
Loosen the four inner
capscrews that hold the
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bearing housing cap to the
bearing cartridge first. It is
difficult to keep the bearing
cartridge from rotating if the
four outer capscrews have
been removed.
Remove the four outer
capscrews that hold the
bearing cartridge or inner
bearing cap to the end
bracket.
Remove all the capscrews
that hold the non-drive end
bracket to the frame.
Thread two of the capscrews
into the jacking holes in the
end bracket horizontal
center line. Screw these
capscrews in to pull the end
bracket pilot from the
locating recess in the main
generator frame.
Tap the end bracket lightly
while turning the jacking
screws in. Check to make
sure the bearing cartridge is
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not stuck in the end bracket.
CAUTION
The main exciter stator is
attached to the end bracket
and comes out when the end
bracket is removed. Use
extreme care not to damage
the main exciter stator as the
end bracket is removed.
WARNING
This component weighs 23
kg [50 lb] or more. To reduce
the possibility of personal
injury, use a hoist or get
assistance to lift this
component.
The end bracket must be
supported as it is removed from
the bearing cartridge.
Remove the capscrews that
hold the bearing cap to the
bearing cartridge.
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Remove the bearing cap.
Remove the large snap ring
from the generator shaft.
CAUTION
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Use two or more flat
washers or a spacer
between the puller and the
end of the shaft to avoid
damaging the threads in
the end of the shaft.
Use a puller to remove the
bearing.
Press the old bearing from
the bearing cartridge.
The outer race of the
bearing is lightly pressed
into the bearing cartridge.
Remove the bearing outer
race.
Clean and Inspect for Reuse
WARNING
When using solvents, acids,
or alkaline materials for
cleaning, follow the
manufacturers
recommendations for use.
Wear goggles and protective
clothing to reduce the
possibility of personal injury.
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WARNING
Wear appropriate eye and
face protection when using
compressed air. Flying
debris and dirt can cause
personal injury.
Clean the bearing cap and
bearing cartridge using solvent.
Dry using compressed air.
Inspect the bearing cartridge
and bearing caps for cracks,
fretting or other signs of
damage.
If damage is present replace
the bearing cartridge caps.
Install
Pack 27 ml [1 fluid oz] of the
recommended lubricant into
the bearing and put the
same amount of lubricant
into the bearing cartridge
and end cap.
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Sealed bearings are also an
option.
CAUTION
When installing the bearing
in the cartridge, press on the
outer race of the bearing to
avoid damaging the bearing.
WARNING
To reduce the possibility of
personal injury, use
insulated gloves to handle
the hot bearing cartridge.
Heat the bearing cartridge in an
oven to 100°C [212°F] for one
hour.
Press the bearing into the
bearing cartridge.
NOTE: The maximum oven
temperature should not
exceed 120°C [248°F]
Heat the bearing cartridge in
an oven to 100°C [212°F] for
two hour.
Apply a thin coating of clean
engine oil to the generator
shaft.
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WARNING
To reduce the possibility of
personal injury, use
insulated gloves to handle
the hot bearing cartridge.
Using insulated gloves, install
the bearing onto the shaft.
Quickly push the bearing onto
the shaft until it seats against
the shaft shoulder. The bearing
must slide on the shaft and be
seated without excessive force.
CAUTION
Apply pressure to only the
inside race of the bearing.
Applying pressure to the
outer bearing race will
damage the bearing.
If the bearing binds on the
shaft before being fully
seated, use a length of pipe
with an inside diameter slightly
larger that the shaft diameter
to drive the bearing against
the shaft seat. Apply pressure
to the inner race of the
bearing only.
Install the snap ring onto the
shaft next to the inner
bearing race.
Make sure the snap ring is
seated in the groove.
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Install the bearing cap.
NOTE: Make sure that the
end plug of the three wire
harness is attached to the
permanent magnet exciter
stator is through the end
bracket and the harness is
retained by the internal
wire clamp. The harness is
difficult to install with the
end bracket is on the
generator.
Install the end bracket onto
the bearing cartridge.
WARNING
This component weighs 23
kg [50 lb] or more. To reduce
the possibility of personal
injury, use a hoist or get
assistance to lift this
component.
Place a sling around the exciter
mounting surface and lift the
end bracket and rotor to pilot
the end bracket into the
generator frame recess.
Install the end bracket
capscrews.
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Tap the end bracket with a
dead-blow hammer as the
capscrews are tightened
End
[45 ft-
Bracket 60 n.m
lb]
Capscrews
Align the bearing cartridge
threaded capscrew holes
with the holes in the end
bracket by turning the
bearing cap. The bearing
cartridge will rotate in the
end bracket.
Install the bearing cartridge
capscrews.
End
[35 ft-
Bracket 45 n.m
lb]
Capscrews
Pull the main exciter leads
(X and XX) and the
permanent magnetic exciter
stator leads (P2, P3 and P4)
through the hole in the frame
terminal box.
Connect the leads to the
corresponding terminals on
the auxiliary terminal block.
Install the permanent
magnetic exciter. Refer to
Procedure 021-030.
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Install the non-drive end
access cover, the terminal
box sides, lid and support
brackets.
Last Modified: 14-Dec-2007
Copyright © 2000-2010 Cummins Inc. All rights reserved.
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