FILTER 35-8548091

Function and technical context

The 35-8548091 Breather Filter is a critical component of the crankcase ventilation system on Mercury, Mariner and Mercruiser engines. Its mission is to allow the gases and vapors generated inside the engine to be expelled in a controlled manner, while simultaneously preventing the entry of ambient humidity, sea salt and contaminants into the interior of the block. This filter works in continuous contact with the most aggressive conditions of a boat: saline environment, temperature variations and differential pressure. Without adequate protection at this point, internal corrosion and the accumulation of water deposits seriously compromise the useful life of the engine and reliability in navigation.

When to replace this part?

A clogged or damaged breather filter can cause excessive pressure in the crankcase, oil leaks through seals and gaskets, and moisture ingress that generates rust on cylindrical walls and connecting rods. It is recommended that this filter be inspected during each seasonal inspection and replaced if there is visible salt buildup, corrosion or deformation in the mesh. Changing the filter preventively is an economical measure that avoids costly repairs resulting from internal oxidation and premature engine degradation.

Engine Compatibility

Mercury/MerCruiser

Equivalent manufacturer part numbers