ENGINE COOLANT
Use a Long Life Coolant (LLC) that meets or
exceeds the following guidelines and
specifications:
Note: In the U.S., LLC is required for the
warranty to be valid.
• ASTM D3306, D4985 (US)
• JIS K-2234 (Japan)
• SAE J814C, J1941, J1034 or J2036
(International)
NOTICE: Following the manufacturer’s
recommendations, use a proper LLC which
will not have any adverse effects on the
materials (cast iron, aluminum, copper, etc.)
of the engine’s cooling system. See Engine
Coolant Specifications on page 33.
ALWAYS use the mixing ratios specified by
the antifreeze manufacturer for the
temperature range.
NOTICE: ALWAYS add LLC to soft water –
especially when operating in cold weather.
NEVER use hard water. Water should be
clean and free from sludge or particles.
Without LLC, cooling performance will
decrease due to scale and rust in the coolant
system. Water alone may freeze and form
ice; it expands approximately 9% in volume.
Use the proper amount of coolant
concentrate for the ambient temperature as
specified by the LLC manufacturer. LLC
concentration should be a minimum of 30%
to a maximum of 60%. Too much LLC will
decrease the cooling efficiency. Excessive
use of antifreeze also lowers the cooling
efficiency of the engine. NEVER mix
different types or brands of LLC, as a
harmful sludge may form. Mixing different
brands of antifreeze may cause chemical
reactions, and may make the antifreeze
useless or cause engine problems.
Replace the engine coolant periodically,
according to the maintenance section in this
Operation Manual.
Remove scale from the cooling system
periodically by flushing the system.
BEFORE YOU OPERATE
6LY3 LDC Operation Manual
29
© 2008 Yanmar Marine International