The short answer: after every saltwater trip, run fresh water through your outboard's cooling system using flushing muffs, a flush bag or the engine's built-in flush port, following your engine manufacturer's procedure. Adding an engine flush treatment helps remove salt deposits that plain water leaves behind.
Why flushing matters
Saltwater runs through the cooling passages every time you use the motor. When it dries, salt crystals build up, restrict water flow and corrode the inside of the engine. A thorough flush after every trip is one of the cheapest ways to protect an expensive outboard.
What you'll need
- Engine Flush, Salty Captain's outboard and PWC salt removal treatment
- The Captain's Musket Foam & Flush Gun, to feed Engine Flush into the water flow
- Your engine's flushing attachment (muffs, flush bag or flush port)
The Engine Flush Kit combines Engine Flush with the Captain's Musket.
Step by step
- Check your manual. Flushing procedures differ by brand and model. Many outboards need water flowing before you start the engine.
- Connect your flushing attachment and the Captain's Musket to a garden hose.
- Flush with fresh water, then use the Musket to introduce Engine Flush at the dilution on the label.
- Run for the time your manufacturer recommends, checking that the tell-tale stream is flowing.
- Finish with fresh water, then turn off the engine and water in the order your manual specifies.
- Wash the outside of the leg and cowling with Salt Wash.
FAQs
Will flushing fix existing corrosion?
No. Flushing removes salt and helps prevent future corrosion, but it won't repair damage that's already there.
Does this work for jet skis?
Engine Flush is made for outboards and PWCs. Follow your jet ski manufacturer's flushing procedure. See our jet ski cleaning products.
For the full after-trip routine, see how to wash and flush a boat after saltwater.
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