Mercury MerCruiser MCM 4.3L ALPHA Service Manual page 30

MAINTENANCE
Seawater section of cooling system MUST BE COMPLETELY drained for winter
storage, or immediately after cold weather use, if the possibility of freezing temper-
atures exists. Failure to comply may result in trapped water causing freeze and/or
corrosion damage to engine.
When running engine with boat out of water, be certain that area in vicinity of
propeller is clear and that no person is standing nearby. As a precautionary
measure, it is recommended that the propeller be removed.
DO NOT run engine above 1500 rpm, as suction created by seawater pickup pump
may collapse water supply hose and cause engine to overheat.
Be sure that engine compartment is well ventilated and that no gasoline vapors are
present to prevent the possibility of a FIRE or EXPLOSION.
IMPORTANT: Observe the following information to ensure complete draining of cool-
ing system.
• Engine must be as level as possible.
• A wire should be repeatedly inserted into all drain holes to ensure there are no
obstructions in passages.
IMPORTANT: To prevent threads in manifolds, elbows and cylinder blocks from rust-
ing during storage, reinstall drain plugs. Never leave drain plugs out during storage.
NOTE: If possible, place a container under drains and hoses to prevent water from draining
into boat.
Index
Page 1B-30
CAUTION
WARNING
CAUTION
WARNING
SERVICE MANUAL NUMBER 25
90-861328--1 NOVEMBER 1999