Engine Start Circuit; Starter - JLG G5-18A Service Manual

9.6

ENGINE START CIRCUIT

9.6.1

Starter

The starter (1) is located on the left side of the engine
attached to the bell housing.
1
a. Testing the Starter on the Engine
If the starter does not engage when the ignition key
switch is turned, check the following:
1. The transmission control lever is in (N) NEUTRAL
and the park brake switch is set.
2. The main fuse may be blown, requiring replacement.
Check for the cause of the blown fuse.
3. There may be a defect in the ignition key switch,
ignition wiring or starter solenoid.
4. Check battery condition. Clean the battery posts and
the connectors at each end of the battery cables.
5. Check for broken wiring and damaged insulation on
the wiring. Replace all broken or damaged wiring.
6. Check all connections at the starter solenoid, key
switch and wiring harness plugs. Clean and tighten
all connections.
7. If the starter still does not operate after these checks
have been performed, check the starting circuit.
b. Starter Circuit Checks
1. Check wires and connections for looseness,
corrosion, damage, etc.
2. If a "whirring" noise is heard but the engine does not
turn over, the starter is spinning but not engaging the
flywheel. The starter drive or solenoid that pushes
G5-18A, 2505
the drive forward to engage the flywheel may be
defective. Missing or damaged teeth on the flywheel
can also prevent the starter from cranking the
engine.
3. If the starter only "clicks" it may indicate that the
battery is discharged, or that there is a loose or
corroded battery cable connection. Check the
battery state of charge and battery condition first,
then check the cables and cable connections.
4. For additional information on the starting circuit,
refer to Section 9.4.4, "Chassis Schematic."
c. Starter Removal
Remove the starter only if it fails. To remove the starter:
1. Open the battery and engine covers.
2. Disconnect the battery negative (-) cable at the
battery negative (-) terminal.
3. Remove the wires from the solenoid stud. Remove
the red, positive (+) battery cable from the starter.
Label and disconnect the wire from the starter
solenoid housing stud. Record how the wires are
MY1890
installed to ensure correct installation later.
4. Loosen, but DO NOT remove, the fasteners
securing the starter to the flywheel housing. Support
the starter securely, as it is relatively heavy and will
fall if not supported.
5. Support the starter and remove the fasteners
securing the starter to the engine. Remove the
negative (-) ground cable from its starter mounting
bolt.
6. Remove the starter (1) from the machine.
d. Starter Cleaning and Drying
1. While the starter is being removed, wipe away any
grease or dirt that has accumulated around the
starter mounting opening.
2. If reinstalling the starter, clean the exterior of the
starter with an approved solvent. DO NOT submerse
the starter or allow the solvent to contact the starter
bushings.
3. Dry the starter with a clean, lint-free cloth.
e. Starter Periodic Maintenance
A starter requires no routine maintenance beyond the
occasional inspection of the electrical connections, which
must be clean and tight.
Electrical System
9-15