Taylor-Dunn SS-025-34, Service And Parts Manual

Page: 64 / 134

Drive Motor
Page 64
SS and MX Models, DC System
MS-534-13
REPAIR
Brushes
Note: It is recommended that all four brushes be replaced
as a set.
Note: The motor must be removed from the vehicle for this
procedure. Refer to Transmission Service section
for information on removing the motor.
The motor must be disassembled to replace the brushes or
the bearings. Refer to Disassembly section for information on
taking the motor apart.
Commutator
Note: The motor must be removed from the vehicle for
this procedure. Refer to Transmission Service
section for information on removing the motor.
1: The armature must be removed from the motor for this
procedure. Refer to Disassembly section for information
on taking the motor apart.
2: Using a lathe, cut the armature just enough to remove
all grooves, depressions or ridges.
3: Measure the diameter of the commutator. If the
commutator is less than the minimum diameter
specified in Service Limits, then the motor must be
replaced.
4: Thoroughly clean all copper debris from between the
commutator segments.
Note: Copper debris in the undercut area can give a
reading of a shorted armature.
5: Measure the commutator undercut depth in 5
places around the commutator. If any one of the
measurements is less than the minimum undercut
depth specified in Service Limits, then the commutator
must be undercut.
6: While still in the lathe, smooth the commutator with fine
emery cloth.
Undercutting the commutator
1: Using a small straight cut saw blade, cut the
commutator insulation to the proper depth. Refer to
undercut depth in Service Limits.
2: Once all segments have been properly undercut, mount
the armature in a lathe and smooth the commutator
with fine emery cloth.
3: Inspect the armature for shorts. Refer to Motor
Inspection section for information on testing the
armature.
Note: Copper debris in the undercut area can give a
reading of a shorted armature.
This section is one section of a complete service
manual. Before starting any procedure, read all
warnings and instructions that are located in the
Service Guidelines chapter.
WARNING
Properly cut and undercut commutator