Yamaha F50 Owner's Manual page 65

Operation
ter and, if possible, rinse the power head un-
der the cowling.
Cruising in muddy or turbid water
Yamaha strongly recommends that you use
the optional chromium-plated water pump kit
(available for V4 and large engines) if you
use the outboard motor in water with a lot of
sediment in it, such as muddy or other turbid
(cloudy) water.
Cruising in acidic water
Water in some areas can be acidic. After op-
erating in such water, flush the cooling pas-
sages with fresh water to prevent corrosion.
Also rinse the outside of the outboard motor
with fresh water.
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