MerCruiser® was the first and only marine propulsion manufacturer to introduce a single-point, air-actuated water draining system. And now, thanks to several additional draining options, MerCruiser has made that same ease and convenience available on every engine in its lineup. By eliminating the risk of freezing water, boaters can extend their season. And while this is not a substitute for complete winterization, it is an example of how MerCruiser is making boating even easier.

Depending on the model, MerCruiser designed several different methods to simplify draining the water from either an Alpha®, Bravo®, inboard, or Horizon™ engine.
Alpha Water Drain System

• Water is removed from the engine in a simple one-step process that any boater can easily perform.

• The process involves using a rotary handle located on top of the engine.

• Simply turn the blue knob two times, and the system is open to drain. Turn the knob back two times, and the system is closed and ready to run again.

Manual Single-Point Drain
Available on all SmartCraft®, Alpha sterndrive models, the innovative single-point drain system is simple to operate and provides a quick, convenient means of draining water from the engine.

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Bravo®/Inboard System
Because of the engine-mounted seawater pump found on Bravo and inboard models, these engines require a little different system, but very simple to operate nonetheless.

HOW TO OPERATE:

• By using the hand-operated air pump that is attached to the engine (or any other air source), simply pump air into the system.
• Once air pressure is adequate, two valves located low on the engine will open and allow the water to drain from the raw-water cooling circuit.
• Two “wink” indicators pop out to tell you that each drain valve has opened, and the water is flowing out of the engine.
• Once water is drained, close the drain valves by simply lifting the ring attached to the pressure pop-off valve that allows the air pressure to escape.

The air-actuated single-point drain system is standard on all Horizon sterndrive and inboard models.
Air-Actuated Single-Point Drain

Standard on the following models:
• 496 MAG HO™, 496 MAG™, MX 6.2 MPI™ Horizon, 350 MAG MPI Horizon Bravo sterndrives
• 8.1S HO™, 8.1S Horizon, MX 6.2 MPI Horizon, 350 MAG MPI Horizon inboards

Optional on:
• MX 6.2 MPI, 350 MAG MPI, 5.0 MPI, 4.3 MPI Bravo sterndrives
• MX 6.2 MPI, 350 MAG MPI inboards
• MX 6.2 MPI, 350 MAG MPI tow sports inboards
Three-Point Manual Drain System

• Hand-removable drain plugs located at the lower front of the engine.
• Water is removed from the engine by simply unscrewing the blue drain plugs—a process that boat owners can easily perform.
• By eliminating the risk of engine damage from freezing water, this feature enables you to extend your boating season into the cold months.
• Standard on all MPI Bravo sterndrive models, except the MX 6.2 MPI Horizon, 350 MAG MPI Horizon, and 496 MAG, which feature the air-actuated single-point drain.
• Standard on the MX 6.2 MPI and 350 MAG MPI inboard models.
• Standard on the MX 6.2 MPI and 350 MAG MPI tow sports inboard models.


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Multiple-Point Manual Drain System

• The same type of hand-removable blue drain plugs that are on the “three-point manual drain system” are also featured on the “multipoint manual water drain system.
• Standard on carbureted Alpha (except the 3.0L) and Bravo sterndrive models.
• Standard on 5.7L inboard and 5.7L tow sports inboard models.
• Optional on the MX 6.2 MPI, 350 MAG MPI, 5.0 MPI, and 4.3 MPI Bravo sterndrive models.
3.0L Water Drain System

The MerCruiser 3.0L sterndrive features a unique and simple water drain system that also incorporates a freshwater flush system. The procedure for draining the engine is illustrated below. Check the 3.0L owner’s manual for full instructions and cautions.
Step One:
Turn on the bilge pump or make sure the boat’s drain plug is removed, if the boat is out of the water.

Push quick-release fitting buttons to release fittings on blue drain hoses from bracket.
Step Two:
Pull T-handle up until it contacts the quick-release fittings.
Step Three:
Push down on T-handle to force drain hoses below their connection points to the block. Ensure water is draining and continue until all water has drained from the engine.
Step Four:
Pull T-handle until the quick-connect fittings are within reach. Install quick-connect fittings back onto bracket.
Step Five:
Push down on T-handle and replace into slot on bracket. Turn off bilge pump, if it is on. Your engine is now drained of water. Make sure the next time the engine is started you visually inspect the blue drain hoses to make sure they are connected and not leaking.


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