Oil Seals

Oil seals seal the locations where a rotating shaft exits the engine block — at the crankshaft on both the pulley and flywheel sides. Over the years, the rubber sealing lip dries out, hardens, and wears a groove into the shaft. Every boat owner knows the result: oil streaks beneath the pulley, or oil between the engine and marine transmission. That latter leak in particular is often ignored for too long because replacing it requires removing the transmission and the flywheel.

Care is essential during installation: lightly lubricate the sealing lip with engine oil, press the seal in straight and no deeper than prescribed into the housing, and check the shaft for wear — even a new seal will leak on a worn shaft. If there is a distinct groove in the shaft, position the new seal slightly deeper or shallower so the lip rides on an undamaged section of the shaft.

We supply crankshaft seals and oil seal sets (front and rear) for Solé Diesel (Mini 14 to Mini 55), Vetus (M3.10 to M4.17), Meiki, Beta Marine (Beta 10 to Beta 60), Nanni (N2.10 to N4.50 and 4.105 HE), Universal, and JF Marine Power. Replacing the flywheel-side seal? Be sure to also check the flywheel bush and the crankcase gaskets.