Cleaning and Inspection
1. Use a brush or air to clean the field coils,
armature, commutator, armature shaft, brush
end plate, and drive end housing. Wash all other
parts in solvent and dry the parts.
2. Inspect the armature windings for broken or
burned insulation and unsoldered connections.
3. Check the armature for open circuits and
4. Check the commutator for runout (Figure 10).
Inspect the armature shaft and the two bearings
for scoring and excessive wear. If the
FIG. 10 Checking Commutator Runout
commutator is rough, or more than 0.005 inch
Position the coils and pole pieces, with the coil
out-of-round, turn it down.
leads in the terminal screw slot, and then install
5. Check the brush holders for broken springs and
the retaining screws (Figure 8). As the pole shoe
the insulated brush holders for shorts to ground.
screws are tightened, strike the frame several
Tighten any rivets that may be loose. Replace
sharp blows with a soft-faced hammer to seat
the brushes if worn to 1/4 inch in length.
and align the pole shoes, then stake the screws.
6. Check the brush spring tension. Replace the
Install the solenoid coil and retainer and bend
springs if the tension is not within specified limits
the tabs to retain the coils to the frame.
(40 ounces minimum).
Solder the field coils and solenoid wire to the
7. Inspect the field coils for burned or broken
starter terminal using rosin core solder. Use a
connections and lead insulation. A brush kit and
a contact kit are available. All other assemblies
are to be replaced rather than repaired.
Position the new insulated field brushes lead on
8. Examine the wear pattern on the starter drive
the field coil terminal. Install the clip provided
teeth. The pinion teeth must penetrate to a depth
with the brushes to hold the brush lead to the
greater than 1/2 the ring gear tooth depth (Figure
terminal. Solder the lead, clip, and terminal
11), to eliminate premature ring gear and starter
together, using rosin core solder (Figure 12).
Use a 300-watt iron.
9. Replace starter drives and ring gears with milled,
Position the solenoid coil ground terminal over
pitted or broken teeth or that show evidence of
the nearest ground screw hole.
inadequate engagement (Figure I 1).
Position the ground brushes to the starter frame
and install the retaining screws (Figure 12).
1. Install the starter terminal, insulator, washers,
and retaining nut in the frame (Figure 12). Be
sure to position the slot in the screw
perpendicular to the frame end surface.
FIG. 11 Pinion and Ring Gear Wear Patterns