Chris-Craft 2015 21 Carina Owner's Manual page 147

Closed Cooling Drain And Winterization Check List
1. With the engine turned off locate and loosen the lower
end cap of the heat exchanger. See photo for location
of the exchanger.
2. After the water has completely drained retighten the lower
end cap of the heat exchanger. It is not necessary to remove
the end cap.
3. Remove the drain plugs from the exhaust manifolds. Raise or
lower the bow to ensure complete drainage.
4. After all of the water is completely drained, place the drain
plugs in a plastic bag and attach to the engines.
5. Note the hose orientation of the raw water pump.
Loosen the hose clamps and remove the hoses from
the raw water pump.
6. Crank the engine briefly, one or two crankshaft
revolutions but do not start the engine to clear water
from the pump.
7. Reinstall the hoses and secure the clamps in the same
orientation as they were when removed.
8. Failure to connect the raw water pump hoses in the correct
orientation will damage the water pump impeller.
9. Be sure that all water is drained from the engine.
Failure to drain all water will result in engine freeze damage.
Figure 4-20 Lower End Cap Of Heat Exchanger
Warning: Do not drain anti freeze from
the closed cooling system drain plugs.
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Storage And Commissioning
Figure 4-21. 5.7 Closed Cooling System
Figure 4-22. Heat Exchanger Location
The Fresh Water Cooled Engine is
Shown here. The heat exchanger is
located as shown on the Starboard
side of the engine.
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