Fuel Recommendations - Honda Outboard Motor BF40A/50A Owner's Manual

4. PRE-OPERATION CHECKS
Fuel Recommendations
Use unleaded gasoline with a pump octane rating of 86
or higher.
These outboard motors are certified to operate on unleaded
gasoline. Unleaded gasoline produces fewer engine and spark
plug deposits and extends exhaust system life.
Never use stale or contaminated gasoline or an oiVgaso-
line mixture. Avoid getting dirt or water in the fuel tank.
Occasionally you may hear light "spark knock" or "ping-
ing" (metallic rapping noise) while operating under heavy
loads. This is no cause for concern.
If spark knock or pinging occurs at a steady engine speed,
under normal load, change brands of gasoline. If spark knock
or pinging persists, see an authorized Honda Marine dealer.
1 NOTICE] Running the engine with persistent spark knock
or pinging can cause engine damage.
Running the engine with persistent spark knock or pinging is
misuse, and the Distributor's Limited Warranty does not cover
parts damaged by misuse.
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