Section 5 - Maintenance
90-8M0074347
eng
OCTOBER 2012
Page 69
NOTICE
Air trapped in the closed cooling system can cause the engine to overheat, resulting in engine damage. Minimize the
possibility of trapping air when initially filling the closed cooling system by positioning the boat so that the front of the engine
is higher than the rear of the engine.
NOTE: Add coolant only when the engine is at normal operating temperature.
1. Remove the fill cap from the coolant recovery bottle. Inspect the gasket and replace if necessary.
IMPORTANT: Coolant flows at a high rate of speed in this closed cooling system. Higher idle speeds can trap air in the
system and make purge procedures more difficult. Operate at idle when filling the system or purging air.
2. Fill to the full mark with the specified coolant.
Tube Ref No.
Description
Where Used
Part No.
122
Extended Life Antifreeze/
Coolant
Closed cooling system
92-877770K1
3. Check the antifreeze concentration for adequate freeze protection and correct if necessary. Refer to the
Specifications
section.
4. Install the fill cap to the coolant recovery bottle.
Changing
Contact your authorized Mercury MerCruiser dealer.
Engine Coolant—3.0 TKS
Checking
!
CAUTION
A sudden loss of pressure can cause hot coolant to boil and discharge violently resulting in serious injury from burns. Allow
the engine to cool down before removing the coolant pressure cap.
1. Remove the cap from the thermostat housing and observe the fluid level.
a -
Thermostat housing cap
2. The coolant level in the thermostat housing should be at the bottom of the filler neck. If the coolant level is low, contact
your authorized Mercury MerCruiser dealer.
3. Install the cap onto the thermostat housing.
IMPORTANT: When reinstalling the pressure cap, be sure to tighten it until it seats on the filler neck.
4. With the engine at normal operating temperature, check the coolant level in the coolant recovery bottle.
a
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