Honda FJ500 Manuel De L'utilisateur page 20

7.Transmission gear oil
Place the tiller on a level surface and remove the oil filler cap.
The oil should be level with the lower edge of the oil filler hole.
Add recommended oil if the level is low.
Recommended oil
Use 10W-30 4-stroke motor oil that meets or exceeds the requirements
for API service classification SE or later (or equivalent). Always check
the API service label on the oil container to be sure it includes the
letters SE or later (or equivalent).
OIL FILLER HOLE
TRANSMISSION OIL FILLER CAP
LOWER EDGE OF
THE OIL FILLER HOLE
UPPER LIMIT
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