Mercury MerCruiser D2.8L D-Tronic Service Manual page 746

CLOSED COOLING SYSTEM
Allow engine to cool before removing pressure cap. Sudden loss of pressure could
cause hot coolant to boil and discharge violently causing severe injury.
1. Allow engine to cool. After engine has cooled, turn pressure cap 1/4 turn to allow any
pressure to escape slowly, then push down and turn cap all the way off of heat
exchanger/coolant tank.
2. Drain coolant from intake/exhaust manifold by opening the drain valve.
3. Drain coolant from the engine block by opening the drain valve.
4. After coolant has drained completely, securely close drain valves.
5. Empty coolant recovery bottle.
6. If required, clean system. Refer to Cleaning Closed Cooling System.
7. Fill system with required coolant.
Typical Sterndrive (MCM) Shown, Inboard (MIE) Similar
Page 6B-18
d
72520
a - Pressure Cap
b - Intake/Exhaust Manifold Drain Valve
c - Engine Block Drain Valve
d - Coolant Recovery Bottle
WARNING
b
71364
SERVICE MANUAL NUMBER 22
c
76391
90-860074--1 FEBRUARY 2002
a