Marine experts know that straight water flushing does little to remove damaging salt corrosion.
These salt deposits build up inside the motor and cause damage in two ways - Salt is deposited onto the cooling channel surfaces. Just like hard water mineral deposits on the interior of hot water cylinder pipes, the salt builds up to insulate the cooling system thereby reducing its efficiency. Overheating problems usually result. Pitting corrosion occurs after the salt has broken the surface of the alloy and burrows into the actual motor block. Motor failure results when this process continues through to the cylinders or exterior.