5-B. Next disconnect the three leads fastened under screws and nuts 106, 92, and
94 and take out two screws (91) which hold switch mounting bracket assembly
(105) in motor. Remove this assembly, including the two governor brushes (97)
and resistor (43).
6. Removing
the Armature (27)
Following the work outlined in the preceding sections take out the two
retaining screws (23) and gently tap front housing to help break the lacquer
finish at the point where the front part of the motor case joins the rear part
(28). When the two pieces have been separated the armature may be removed and
a tight bearing located.
7. To Free Tight Motor Bearings (45)
First, thoroughly clean bearing holes by wiping with a clean rag, F1ush out
oil holes and bearings (45) with kerosene fed from the spout of an oil can.
Wipe thoroughly until dry. Rub armature shaft with an oilstone to remove
scoring or roughness, apply oil to the shaft and see that it is free to turn
in either bearing. (NOTE: If bearings are worn, or require replacement for
any reason, return motor to factory for service. Bearings in Model 1 are oil
less-type and must not be reamed.) It is well at this point, since the
armature is out, to test it, and the field coils, for grounds, etc. as
follows.
8. Testing Armature (27) and Field Coils (44)
To check the armature for grounds touch one wire tip of test lamp on the
armature shaft, then touch the other on any commutator bar or bars. If test
lamp lights a ground or conducting path is present between live parts and
laminations, a condition that should not exist, and the armature should be
replaced with a new one. Examine commutator bars to see if there are burned
marks along the edges of any of the bars. Such marks indicate short circuited
winding and armature should be replaced. Also observe if any wires leading
from winding to the commutator are broken or damaged from rubbing on the brush
leads. Replace armature if this condition is found.
Commutator should be smooth without excessive ridges or rings cut in it.
Commutators with excessive rings cut in them by the motor brushes (19)
should be replaced, or if a lathe is available they may be turned down with
a smooth cut.
Check field coils through leads and motor case, for grounds, and through both
leads for open circuit.
9. Assembling
Motor
The armature shaft should be inserted into the back bearing, and the front
housing then slipped part way onto the front of the armature shaft. The brush
lead wires with the clips should be clipped onto the brush holders (18). The
lead and clip coming direct from the field coil (44) should put on the brush
holder on the right, and the lead and clip from the condenser on brush holder
on the left, as the workman looks at the back of the motor, After the brush
clips are put on the brush holders and the lead wires are carefully arranged
not to rub against the armature, and when the condenser (69) has been started
into the space provided for it in the
