Starting System - Yanmar 1GM User Manual

TROUBLESHOOTING
STARTING CIRCUIT (TYPICAL)
Starter solenoid
Starter switch
- - - - + t
Key switch
Battery
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service, as well as to provide a measure of safety that is
not required ofautomotive service. For example, a marine
starter is flashproofed to prevent possible ignition of fuel
vapor in the bilge. The use ofan automotive starter as a re-
placement can result in an explosion or fire, which may
cause death, serious injury or boat damage.
This chapter contains brief descriptions of each major
operating system and troubleshooting procedures to be
used. The troubleshooting procedures analyze common
symptoms and provide logical methods of isolation.
These are not the only methods. There may be several ap-
proaches to a problem, but all methods used must have
one thing in common to be successful-a logical, system-
atic approach.
Troubleshooting diagrams for individual systems are
provided within this chapter. A master troubleshooting
chart (Table 1) is provided at the end of this chapter.
STARTING SYSTEM
The starting system consists of the battery, starter mo-
tor, starter solenoid, starter switch, key switch, fuse and
connecting wiring. See Figure 1, typical.
Starting system problems are relatively easy to find. In
many cases, the trouble is a loose or dirty connection.
Starting System Operation
The battery switch, ifused, and the key switch must be
in the ON positions so battery current is available to the
starter circuit. When the start switch on the instrument
panel is pushed, battery current flows to the starter sole-
noid, which mechanically engages the starter with the en-
gine flywheel. The solenoid also directs current to the
starter motor, which rotates the engine flywheel to start