Specifications; Seacock; Seawater Strainer; Anti-Freeze/Coolant - Mercury D4.2L Manual

CD7
CD11

Seacock

Seacock (water inlet valve) used, must have an internal cross-sectional area equal to or greater than hose to
prevent restricting water flow. A 1-1/2 in. (38mm) brass ball or gate valve is minimum required.
Seacock should be installed in an area where it is easily accessible and supported adequately to prevent hose
fatigue.
CE14

Seawater Strainer

Seawater Strainer should be provided, and be of sufficient size to ensure that an adequate supply of water will
be maintained for cooling engine. A minimum flow rate of 40 gallons (150 litres) per minute is required.
Strainer should be installed in an area where it will be easily accessible for inspection and cleaning. Strainer
should be installed in water inlet hose after seacock to allow operator to shut off water inlet when cleaning strainer.
CD535

Anti-Freeze/Coolant

Alcohol or Methanol base antifreeze or plain water are not recommended for use in closed cooling
section of cooling system at any time.
Because diesel engines are high compression engines and related higher engine operating temperatures are
created, the closed cooling system and engine, including related cooling passages must remain as clean as pos-
sible to provide adequate engine cooling. This can only be assured by using the proper anti-freeze, water, additives
and inhibitors. It is recommended that the closed cooled section of the cooling system be filled with a low, or no,
silicate formula of ethylene glycol antifreeze in solution with deionized water. A low silicate formula prevents anti-
freeze separation which causes a silicate gelatin to form. This gelatin will block engine and heat exchanger pas-
sages causing engine overheating.
The coolant, if not premixed, should be mixed before being added to the closed cooling system using a proper
anti-freeze together with deionized water. Common tap water or softened water contains unwanted minerals
which can leave large deposits in the system that restrict the cooling system efficiency. In addition, additives and
inhibitors introduced into acceptable coolant solutions will form a protective film on internal passages and pro-
vide protection against internal cooling system erosion.
The closed cooling section should be kept filled year-round with an acceptable anti/freeze/coolant solution. Do
not drain closed cooled section for storage, as this will promote rusting of internal surfaces. If engine will be ex-
posed to freezing temperatures, make sure that closed cooled section is filled with a properly mixed antifreeze/
coolant solution, to protect engine and closed cooling system to lowest temperature to which they will be ex-
posed.
IMPORTANT: The anti-freeze/coolant used in these marine engines must be a low (or no) silicate ethylene
glycol, containing special additives, and deionized, purified water. Using other types of engine coolant
may cause fouling of the heat exchangers, and overheating of the engine. Do not combine different types
of coolants without knowing that they are compatible. Refer to the coolant manufacturer's instructions.
Some acceptable types of anti-freeze/coolants are listed in the following table. Refer to "Maintenance Schedules"
for respective change intervals.
Quicksilver Premixed Marine Engine Coolant
Fleetguard Complete

Specifications

CAUTION
DESCRIPTION PART NUMBER
92-813054A2
Obtain Locally
57