Electrical System; Battery; Electronic Ignition Systems; Battery Size Recommendations - Kohler CH940-CH1000 Service Manual

Electrical System

Battery

A 12-volt battery with 400 cold cranking amps (cca) is
generally recommended for starting in all conditions. A
smaller capacity battery is often suffi cient if an
application is started only in warmer temperatures. Refer
to following table for minimum capacities based on
anticipated ambient temperatures. Actual cold cranking
requirement depends on engine size, application, and
starting temperatures. Cranking requirements increase
as temperatures decrease and battery capacity shrinks.
Refer also to operating instructions of equipment this
engine powers for specifi c battery requirements.

Electronic Ignition Systems

There are two different types of ignition systems used on these engines. All systems use an ignition module which
energizes spark plug. Difference in system is in way ignition timing is triggered.
Fixed Ignition System
This engine uses a capacitive discharge (CD) coil where ignition timing and spark remains constant regardless of
engine speed. Timing of spark is controlled by location of fl ywheel magnet group as referenced to engine top dead
center. A typical fi xed ignition system consists of:
● A magnet assembly which is permanently affi xed to fl ywheel.
● Two electronic capacitive-discharge ignition modules which mount on engine crankcase.
● A kill switch (or key switch) which grounds modules to stop engine.
● Two spark plugs.
Digital Spark Advance Ignition (DSAI) System
This system uses a digital microprocessor which is located in ignition modules. Ignition timing varies depending upon
engine speed with this system. Two inductive-style ignition modules control ignition timing based on engine RPM. A
typical DSAI application consists of:
● A magnet assembly, which is permanently affi xed to fl ywheel.
● Two inductive, 12-volt ignition modules, which mount on engine crankcase.
● A 12-volt battery, which supplies current to ignition modules.
● A kill switch (or key switch) which grounds spark advance module to stop engine.
● Two spark plugs.
Both ignition systems are designed to be trouble free for life of engine. Other than periodically checking/replacing
spark plugs, no maintenance or timing adjustments are necessary or possible. Mechanical systems do occasionally
fail or break down. Refer to troubleshooting to determine root of a reported problem.
Reported ignition problems are most often due to poor connections. Before beginning test procedure, check all
external wiring. Be certain all ignition-related wires are connected, including spark plug leads. Be certain all terminal
connections fi t snugly. Make sure ignition switch is in run position.
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Battery Size Recommendations

Temperature
Above 32°F (0°C)
0°F to 32°F (-18°C to 0°C)
-5°F to 0°F (-21°C to -18°C)
-10°F (-23°C) or below
If battery charge is insuffi cient to turn over engine,
recharge battery.
Battery Maintenance
Regular maintenance is necessary to prolong battery
life.
Battery Test
To test battery, follow manufacturer's instructions.
KohlerEngines.com
Battery Required
300 cca minimum
300 cca minimum
300 cca minimum
400 cca minimum
62 690 01 Rev. C