Regal 3300 Owner's Manual page 84

CHAPTER 3
Engine Oil
The purpose of engine oil is to lubricate the internal components of
the engine and ensure that parts that regularly move against each other
have reduced friction to reduce wear and noise between components.
An oil filter keeps metal particles and water out of the engine's interior.
Gearcase Oil
Gearcase oil keeps all the mechanical components of the propshaft
gear assembly functioning optimally. It reduces friction in the gearcase
as the gears revolve. Sometimes gearcase oil is called gear lubricant,
as the oil essentially lubricates the gears inside the gear box. Gearcase
oil should be inspected periodically according to factory maintenance
schedules. Use outboard manufacturer's recommended oil.
Power Trim Fluid
Power trim fluid allows your outboard to trim up or down. This is
particularly useful when trying to get your boat to plane where the hull
is as much out of the water as physically possible, reducing friction,
and improving ride performance. This power trim fluid is used in
hydraulic rams that maneuver the outboard unit, and shouldn't need
to be replaced very often, if at all.
Power trim fluid should be checked regularly, despite not requiring
replacement unless something serious happens. Discoloration or water
presence indicates a water leak in the system. In that case, contact your
Regal dealer. Use outboard manufacturer's recommended fluid.
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