Mercury 25 2-Stroke, Owner'S Manual

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FUEL & OIL
53
The fuel system components on your Mercury Marine engine will
withstand up to 10% alcohol content in the gasoline. We do not
know what percentage your boat's fuel system will withstand.
Contact your boat manufacturer for specific recommendations on
the boat's fuel system components (fuel tanks, fuel lines, and
fittings). Be aware that gasolines containing alcohol may cause
increased:
• Corrosion of metal parts
• Deterioration of rubber or plastic parts
• Fuel permeation through rubber fuel lines
• Starting and operating difficulties
!
WARNING
Fuel leakage is a fire or explosion hazard, which can cause
serious injury or death. Periodically inspect all fuel system
components for leaks, softening, hardening, swelling, or
corrosion, particularly after storage. Any sign of leakage or
deterioration requires replacement before further engine
operation.
Because of possible adverse effects of alcohol in gasoline, it is
recommended that only alcohol‑free gasoline be used where
possible. If only fuel containing alcohol is available, or if the
presence of alcohol is unknown, increased inspection frequency
for leaks and abnormalities is required.
IMPORTANT: When operating a Mercury Marine engine on
gasoline containing alcohol, storage of gasoline in the fuel tank for
long periods should be avoided. Long periods of storage, common
to boats, create unique problems. In cars, alcohol‑blend fuels
normally are consumed before they can absorb enough moisture
to cause trouble, but boats often sit idle long enough for phase
separation to take place. In addition, internal corrosion may take
place during storage if alcohol has washed protective oil films from
internal components.
Oil Recommendation
Recommended Oil
Mercury or Quicksilver Premium 2-Cycle TC-W3
Outboard Oil