INBOARD OIL 4T 25W40 1L

Function and technical context

This 25W40 multigrade lubricant for four-stroke inboard engines acts as a protective barrier between the moving components of the engine block, reducing friction in the crankshaft, camshaft, pistons and bearings. Formulated to work in the pressure lubrication system of stationary marine engines, it maintains a stable viscosity both in cold starts and under sustained thermal load in navigation. It meets API SJ, CF-2 and CH-4 specifications, ensuring its suitability for both marine petrol and diesel engines. Inadequate or degraded oil causes accelerated wear of internal components, loss of compression, overheating and, in extreme cases, engine seizure.

When to change the oil?

The most common symptoms that indicate that the lubricant has lost its properties are increased oil consumption, intense blackish color or milky appearance (a sign of water contamination), metallic noises at idle and unstable oil pressure on the pressure gauge. In marine inboard engines, it is recommended to change it every 100 hours of navigation or at the beginning of each season, whichever comes first, following the engine manufacturer's guidelines. Taking advantage of the oil change to simultaneously replace the oil filter is the most common practice among naval mechanics to guarantee a clean lubrication system from the first use.

Compatibility table