4-CYCLE OVERHEAD VALVE ENGINES - Small Engine Discount

Inspection And Repair
1. The pinion gear parts should be checked for
damage or wear. If the gear does not engage
or slips, it should be washed in solvent (rubber
parts cleaned in soap and water) to remove dirt
and grease, and dried before reassembly. Also
check the armature and drive nut splines for
wear or damage. Replace parts as necessary.
2. The brushes and brush card holder should be
checked for wear. With the armature in place
and the brushes engaging the commutator
surface, check the brushes for wear. Brushes
should be replaced if the brush wire approaches
the bottom of the brush holder slot. Brush
springs must exhibit enough strength to keep
tension on the brushes and hold them on the
commutator.
3. The field windings can be checked using a
continuity light or ohmmeter. Attach one lead
to each field coil connection. Continuity should
exist between each field coil connection, and
no continuity should exist between the field coil
connections and the starter housing (diag. 32
& 33).
4. The armature should be checked for glazing or
wear. If necessary the armature can be turned
down in a lathe. While rotating, polish the
commutator bars using a piece of 00 sandpaper
(diag. 34). Light pressure and back and forth
movement should be used. Recut the
commutator bars to a depth equal to the width
of the insulators between the bars. Check for
continuity between the copper commutator bars
and the iron of the armature, none should exist
(diag. 35).
FIELD COIL
CONNECTORS
BRUSH
SPRINGS
FIELD COIL
CONNECTORS
CONNECTION POINT OF
POWER CORD LEADS
12 VOLT 32
120 VOLT
33
34 35
Brush Card Replacement
1. Loosen but do not remove the two nuts on the starter terminal post.
2. Remove the nuts holding the end cap in place. Remove the end cap and the thrust washer.
3. Grasp the thru bolts using a vise grip positioned as close to the flanged end as possible to prevent
thread damage. Remove the two nuts holding the driving end cap in place. Remove the armature and
driving cap assembly, followed by the two thru bolts. Notice the position of the brush ground eyelet under
the thru bolt flange.
4. Note or mark the position of the connectors of the brush wires. Use a wire cutter to clip the solid field
wires as close to the connectors as possible.
5. Note or mark the brush card in the starter housing, and remove the brush card assembly. Clean the
accumulated dirt off all starter parts. Scrape the insulating varnish off the last 1/2" (12.7 mm) of the solid
field wires.
6. Insert the new brush card into position while guiding the solid field wires through the proper slots in the
brush card.
7. Crimp and solder the brush leads to the solid field wires. Use a needle nose pliers or vise grip to hold the
woven brush lead close to the connector while soldering. This prevents solder and heat from flowing up
the brush lead. Insulate the crimped connection nearest the starter terminal post using electrical tape or
heat shrink tubing. Route the wires to prevent damage during assembly.
8. Install the armature into the housing while spreading the brushes. Install the thru bolts while checking to
make sure the bolts go thru the ground brush eyelet terminals. Install and tighten the drive end thru bolt
nuts, but do not overtighten.
9. Install the thrust washer on the end of the armature and the install the starter end cap. Secure the cap
with the locking nuts and tighten the nut on the starter terminal post. Rotate the armature by hand to
check for binding before installation on the engine.
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