TM9-4120-400-14
5-8.
a. To replace connector (1):
(1) Loosen cable clamp (2).
(3) Remove old connector (1).
(4) See wiring diagram figure 4-4 and tags and solder leads to new connector (1). Remove tags.
(5) Secure cable clamp (2).
b. To replace bearings:
(1) Match mark stator (3) and both end brackets (4 and 5) to ease reassembly.
(2) Remove four screws (6) each from front and rear brackets (4 and 5).
(3) Carefully separate end brackets (4 and 5) from stator (3). Using a brass or plastic bar and hammer tap
opposite sides, top and bottom in alternating sequence to break end brackets loose.
(4) Remove end brackets (4 and 5).
(5) Press out or carefully drive bearings (7) out of end brackets. Retain washers (8) and load spring (9)
from front bracket for use at reassembly if they are not damaged.
(6) Examine rotor, stator, and shafts for nicks, gouges, deformations, and evidence of overheating.
(7) Dress high metal defects in shafts with a fine file or stone. If damage beyond repair, replace motor.
(8) Coat shaft surfaces of rotor (10) with oil and slide bearings (7) on shaft ends. They should seat against
shoulders at the inner ends of shaft.
(9) Coat washers (8) and load spring (9) with oil and slide them over end of front shaft with load spring (9)
installed first.
(10) Coat bearing cavity of each end bracket (4 and 5) with oil. Slide end-bracket carefully into position
over shaft so that OD of bearing enters ID of bearing cavity in end-bracket. Work end brackets onto
shaft until bore fits over end of stator (3). Keep match-marks made at time of disassembly in alignment.
(11) Place four screws (6) in each end bracket (4 and 5).
(12) Tap around both end brackets (4 and 5) with a plastic or rawhide mallet while tightening screws (6).
Tighten in alternating sequence until all screws are equally tightened. Check for freedom of rotation
by turning motor shaft by hand. There should be no drag or binding.
(13) Check end play of shaft. End play should be 0.002-0.005 inch (0.051 - 0.127 mm). If end-play is not
within limits, disassemble motor and add or remove shims to adjust.
5-23