Cold Weather Or Extended Storage; Preparing Power Package For Storage; Engine And Fuel System Preparation - Mercury 350 MAG Manual

Section 6 - Storage

Cold Weather or Extended Storage

IMPORTANT: Mercury MerCruiser strongly recommends that this service should be performed by an authorized Mercury
MerCruiser dealer. Damage caused by freezing temperatures IS NOT covered by the Mercury MerCruiser Limited Warranty.
Water trapped in the seawater section of the cooling system can cause corrosion or freeze damage. Drain the seawater section
of the cooling system immediately after operation or before any length of storage in freezing temperatures. If the boat is in the
water, keep the seacock closed until restarting the engine to prevent water from flowing back into the cooling system. If the boat
is not fitted with a seacock, leave the water inlet hose disconnected and plugged.
NOTE: As a precautionary measure, attach a tag to the key switch or steering wheel of the boat reminding the operator to open
the seacock or unplug and reconnect the water inlet hose before starting the engine.
IMPORTANT: Mercury MerCruiser requires that propylene glycol antifreeze, mixed to the manufacturers instructions, be used in
the seawater section of the cooling system for freezing temperatures or extended storage. Make sure that the propylene glycol
antifreeze contains a rust inhibitor and is recommended for use in marine engines. Be certain to follow the propylene glycol
manufacturer's recommendations.

Preparing Power Package for Storage

1. Fill the fuel tanks with fresh gasoline (that does not contain alcohol) and a sufficient amount of Quicksilver Gasoline Stabilizer
for Marine Engines to treat the gasoline. Follow instructions on the container.
2. Check the antifreeze concentration. Refer to the Specifications section.
3. If the boat is to be placed in storage with fuel containing alcohol in fuel tanks (if fuel without alcohol is not available): Fuel
tanks should be drained as low as possible and Mercury/Quicksilver Gasoline Stabilizer for Marine Engines added to any fuel
remaining in the tank. Refer to Fuel Requirements for additional information.
4. Flush the cooling system. Refer to the Maintenance section.
5. Supply cooling water to engine. Refer to the Maintenance section
6. Operate the engine sufficiently to bring it up to normal operating temperature and allow fuel with Mercury/Quicksilver Gasoline
Stabilizer to circulate through the fuel system. Shut off the engine.
7. Change the oil and oil filter.
8. Prepare the engine and fuel system for storage. See Engine and Fuel System Preparation.
9. Drain the engine seawater cooling system. See Draining the Seawater System.
Water trapped in the seawater section of the cooling system can cause corrosion or freeze damage. Drain the seawater section
of the cooling system immediately after operation or before any length of storage in freezing temperatures. If the boat is in the
water, keep the seacock closed until restarting the engine to prevent water from flowing back into the cooling system. If the boat
is not fitted with a seacock, leave the water inlet hose disconnected and plugged.
10. For additional assurance against freezing and rust, after draining, fill the seawater cooling system with propylene glycol mixed
to the manufacturer's recommendation to protect engine to the lowest temperature to which it will be exposed during freezing
temperatures or extended storage.
11. Store the battery according to the manufacturer's instructions.

Engine and Fuel System Preparation

Fuel is flammable and explosive. Ensure that the key switch is off and the lanyard is positioned so that the engine cannot start.
Do not smoke or allow sources of spark or open flame in the area while servicing. Keep the work area well ventilated and avoid
prolonged exposure to vapors. Always check for leaks before attempting to start the engine, and wipe up any spilled fuel
immediately.
Fuel vapors trapped in the engine compartment may be an irritant, cause difficulty breathing, or may ignite resulting in a fire or
explosion. Always ventilate the engine compartment before servicing the power package.
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NOTICE
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WARNING
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90-8M0050539 MAY 2011
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