High RPM Marine Engine

August 26, 2021

Image by Herbert Aust from Pixabay

High RPM Marine Engine

Marine engine oil is constantly under load. AMSOIL manufactures high rpm marine engine oil for 4-cycle water cooled (*NMMA FC-W) engines. Our customers find better throttle response and overall engine performance.

Jetski Image by Herbert Aust from Pixabay… Thank you Herbert! …

The typical marine engine will run about 5000 rpm at 30 mph compared to an automobile engine that runs at about 2000 rpm at 60 mph. Unlike an automobile engine that eases its load with coasting or downhill travel a marine engine rarely coasts. High heat and high rpm can easily break down the oil’s viscosity causing it to become thinner. Thinner oil can no longer separate moving parts from wear and friction. AMSOIL’s extreme film strength resist viscosity shear for longer lasting lubrication of moving parts eliminating metal to metal contact. Engines run quieter and perform their best so you get the most power and performance from you engine all season long. For high-rpm running engines, AMSOIL keeps inboard/ outboard engines and personal watercraft engines running their best.

*AMSOIL 4-stroke oil for marine engines are certified by the National Marine Manufacturers Association (NMMA), meeting the requirements of Four Cycle – Water-cooled (NMMA FC-W) Catalyst Compatible specification, which is backward-compatible with the FC-W specification.

Our customers ask: “My Mercury owner’s manual specifies a synthetic-blend, which AMSOIL products should I use?

AMSOIL Technical: “Mercury’s owner’s manual discourages the use of full-synthetic and most owners will not consider straying from these guidelines. So AMSOIL designed  “WCM” Marine synthetic-blend Engine Oil SAE 25W-40.


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