MerCruiser 305 CID (5.0L), Руководство по обслуживанию

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CLOSED COOLED MODELS SERVICE MANUAL NUMBER 24
Page 6B-4 90-861327--1 OCTOBER 1999
Before starting engine each day, ensure that coolant is visible in coolant recovery bottle.
If coolant is not visible, check fresh water section of cooling system (including coolant recov-
ery system) for leaks and repair. Refill fresh water section with recommended coolant solu-
tion as outlined under “Changing Coolant,” following.
If coolant is visible, start engine and run until it reaches normal operating temperature, then
recheck coolant level in coolant recovery bottle. Coolant level MUST be between the ADD
and FULL marks (on front of bottle).
WARNING
Allow engine to cool before removing pressure cap. Sudden loss of pressure could
cause hot coolant to boil and discharge violently. After engine has cooled, turn cap
1/4 turn to allow any pressure to escape slowly, then push down and remove cap.
If level is low, remove fill cap from coolant recovery bottle and add required amount of cool-
ant solution. Refer to “Coolant recommendations” in this section.
IMPORTANT: ALCOHOL OR METHANOL BASE ANTIFREEZE OR PLAIN WATER ARE
NOT RECOMMENDED FOR USE IN COOLING SYSTEM AT ANY TIME. In areas where
ethylene glycol is not available, and the possibility of freezing does not exist, it is
permissible to use a solution of rust inhibitor and pure, soft water (mixed to
manufacturer’s recommendations).
Occasionally, ensure that coolant recovery system is functioning properly by removing
pressure cap from heat exchanger and checking level. Coolant level should be up to bottom
of heat exchanger filler neck. If low, examine entire fresh water section (especially coolant
recovery system) for leaks and repair.
IMPORTANT: When reinstalling pressure cap, tighten it until it contacts stops on filler
neck.
Pressure Cap Maintenance
Pressure cap should maintain pressure in fresh water section of closed cooling system at
normal engine operating temperature. This raises the boiling point of the coolant, thereby
increasing the efficiency of the cooling system. To help ensure proper operation, cap should
be cleaned, inspected and pressure tested periodically as follows:
WARNING
Allow engine to cool before removing pressure cap. Sudden loss of pressure could
cause hot coolant to boil and discharge violently. After engine has cooled, turn cap
1/4 turn to allow any pressure to escape slowly, then push down and turn cap all the
way off.
1. Remove pressure cap from heat exchanger.
2. Wash cap with clean water to remove any deposits or debris from sealing surfaces.
3. Inspect rubber seal on cap for cuts, cracks or other signs of deterioration. If seal is dam-
aged, cap MUST be replaced.
4. Inspect coolant recovery gasket for deterioration and replace if bad.
Index