Honda GX22 Owner's Manual page 29

4. With the engine in a level position, fill to the edge of the oil filler hole
with the recommended oil (see page 28).
Add the engine oil slowly to avoid overflowing, as the engine oil
tank capacity is small.
Engine oil capacity:
Running the engine with a low or excessive oil level can cause
engine damage.
5. Reinstall the oil filler cap/dipstick securely.
Horizontal type:
SERVICING YOUR HONDA ENGINE
0.11 US qt (0.10 , 0.09 Imp qt)
Vertical type:
UPPER LIMIT
OIL FILLER CAP/DIPSTICK
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