Regal 3300 Owner's Manual page 82

CHAPTER 3
Engine Exhaust System
Your engine expels the by-products of the engine operation through
an exhaust system, just like cars do. In boats however, this exhaust
system mixes the debris left over after the power stroke of the engine
with the hot water that is expelled after cooling the engine.
Basically the exhaust flows through the powerhead before expelling
the exhaust through the vertical drive housing either just above the
propeller, or through the prop shaft.
Engine Electrical System
Spark Plugs
The spark plugs are the piece of equipment that help make ignition
occur. As electrical potential builds on one side of the gap based upon
the energy distributed by the distributor, the potential eventually grows
large enough to cause the electric current to jump the gap on the
spark plug. This spark is what ignites the compressed fuel, generating
a controlled explosion that will power the piston down and deliver
power to the drive shaft.
Stator/Alternator
Under normal circumstances, the starter battery would wear down after
being used so often to generate a spark for the engine. This isn't an
ideal setup because a strong battery is needed for continual operation.
A weak battery does no good out on the water. The stator/alternator
takes care of recharging the battery(ies)
However, in an effort to conserve battery life, the starter battery switch
should still be turned off after every trip and turned on at the start of
every trip. This limits the drain on the battery while the boat is not in
use. The stator will only recharge the battery while the engine is running.
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