Honda BF5A Owner's Manual page 30

6. After starting, check the oil pressure indicator light. The light should be on
while the engine is running. If the light is off, stop the engine immediately,
check the engine oil level, and inspect the engine for oil leaks.
OIL PRESSURE INDICATOR LIGHT
If the oil level is OK, but the light stays off while the engine is running, take
the motor to an authorized Honda marine dealer immediately.
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