Gasoline Requirements for Mercruiser Engines
Revised September, 1994
A. GASOLINE RECOMMENDATION FOR ALL MERCRUISER MARINE ENGINES MODELS USA and Canada
| Model | Gasoline (Notes 2 & 3) | Additives |
|---|---|---|
| 1987 and Newer: V8 350 cid, Except EFI Models. (Note 1) 1990 and Newer: 4 Cyl 181 cid, V8 454, & 502 cid, Except EFI Models. (Note 1) 1991 and Newer: V8 540 & 572 cid, Except Supercharged Models. (Note 1) | 87 (R+M)/2 Minimum Octane Unleaded Regular or Premium Without Alcohol DO NOT USE Leaded Gasoline | None Required |
| EFI: V8 350,454 & 502 cid. (Notes 1 & 4) | 87 (R+M)/2 Minimum Octane Unleaded Regular or Premium Without Alcohol DO NOT USE Leaded Gasoline | None Required |
| V6 and All Other Older 4, 6 Cyl & V8 Models, Except Supercharged Models. | 87 (R+M)/2 Minimum Octane Unleaded Regular or Premium Without Alcohol DO NOT USE Leaded Gasoline | Quicksilver Valve Lubricant |
| Supercharged Models. (Note 1) | 92 (R+M)/2 Minimum Octane Unleaded Premium Without Alcohol DO NOT USE Leaded Gasoline | None Required |
Note 1: The cylinder heads on these engines have hardened exhaust value seat inserts.
Note 2: If gasoline with alcohol must be used, periodically inspect complete fuel system for leaks and do not store fuel in boat’s fuel tank for long periods of time.
Note 3: To increase valve life on all MerCruiser engines, the following recommendations should be considered;
2 Use a propeller that allows engine to operate at or near the top of its maximum RPM range when at full throttle with a normal boat load.
2 Operation at 3/4 throttle setting or lower is recommended. Refrain from prolonged operation at maximum (full throttle) RPM.
Note 4: MCM 5.7L Alpha or Bravo EFI: S/N 0F415136 and Below, MCM/MIE 454 & 502 Magnum Stern Drive or Ski EFI: S/N 0F417515 and Below, MIE 350 Magnum Ski EFI: S/N 0F350545 and Below. USE 87 (R+M)/2 Minimum Octane Unleaded REGULAR Gasoline Without Alcohol. DO NOT USE Premium or Leaded Gasoline.
– 1
A. GASOLINE RECOMMENDATION FOR ALL MERCRUISER MODELS Outside USA and Canada
| Model | Gasoline (Notes 2, 3 & 4) | Additives |
|---|---|---|
| 1987 and Newer: V8 350 cid, Except EFI Models. (Note 1) 1990 and Newer: 4 Cyl 181 cid, V8 454, & 502 cid, Except EFI Models. (Note 1) 1991 and Newer: V8 540 & 572 cid, Except Supercharged Models. (Note 1) | 90 RON Minimum Octane Major Brand of Unleaded Regular or Premium Without Alcohol | None Required |
| EFI: V8 350,454 & 502 cid. (Notes 1 & 5) | 90 RON Minimum Octane Major Brand of Unleaded Regular or Premium Without Alcohol | None Required |
| V6 and All Other Older 4, 6 Cyl & V8 Models, Except Supercharged Models. | 90 RON Minimum Octane Major Brand of Unleaded Regular or Premium Without Alcohol | Quicksilver Valve Lubricant |
| Supercharged Models | 98 RON Minimum Octane Unleaded Premium Without Alcohol | None Required |
Note 1: The cylinder heads on these engines have hardened exhaust valve seat inserts.
Note 2: If gasoline with alcohol must be used, periodically inspect complete fuel system for leaks and do not store fuel in boat’s fuel tank for long periods of time.
Note 3: If unleaded gasoline is not available, use a major brand of leaded gasoline.
Note 4: To increase valve life on all MerCruiser engines, the following recommendations should be considered;
2 Use a propeller that allows engine to operate at or near the top of its maximum RPM range when at full throttle with a normal boat load.
2 Operation at 3/4 throttle setting or lower is recommended. Refrain from prolonged operation at maximum (full throttle) RPM.
Note 5: MCM 5.7L Alpha or Bravo EFI: S/N 0F415136 and Below, MCM/MIE 454 & 502 Magnum Stern Drive or Ski EFI: S/N 0F417515 and Below, MIE 350 Magnum Ski EFI: S/N 0F350545 and Below. USE 90 RON Minimum Octane Unleaded REGULAR Gasoline Without Alcohol. DO NOT USE Premium Gasoline.