How to Flush an Outboard Motor

Regular flushing with freshwater is key to maintaining any outboard motor used in saltwater. Most outboard manufacturers recommend a freshwater flush after every use in saltwater to clear the cooling passages of salt residue and scale that can accumulate and impede the flow of vital cooling water through the engine. Outboards used in brackish water, or in freshwater that’s silty or muddy, should also be flushed.

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