Honda EM3500X Owner's Manual page 11

2. Fuel
Check the fuel meter and refill the tank if the fuel level is low.
Your engine is designed to use any gasoline that has a pump octane
number (y 1 of 86 or higher, or that has a research octane number of
91 or higher. Gasoline pumps at service station normally display the pump oc-
tane number.
We recommend that you use unleaded fuel because it produces fewer engine
and spark plug deposits and extends the life of exhaust system components.
Never use stale or contaminated gasoline or an oil/gasoline mixture. Avoid get-
ting dirt, dust or water in the fuel tank. Use of a lower octane gasoline can
cause persistent "pinging" or heavy "spark knock" (a metallic rapping noise)
which, if severe, can lead to engine damage.
CAUTION: If "spark knock" or "pinging" occurs at a steady engine
speed under normal load, change brands of gasoline. If spark knock or
pinging persists, consult your authorized Honda dealer. Failure to do so
is considered misuse, and damage caused by misuse is not covered by
Honda's Limited Warranty.
Occasionally you may experience light spark knock while operating under heavy
loads. This is no cause for concern, it simply means your engine is operating
efficiently.
Fuel tank capacity: 17.0 Q (4.5 US gal)
FUEL METER
FUEL FILLER CAP
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