Yanmar 3JH4E, Operation Manual

Page: 42 / 142

ENGINE COOLANT
Engine Coolant Specifications
• Texaco Long Life Coolant (LLC), both
standard and premixed, product code
7997 and 7998.
• Havoline Extended Life
Antifreeze / Coolant, product code 7994.
Note: In the U.S., LLC is required for the
warranty to be valid.
Coolant (Closed Cooling System)
NOTICE: Always add LLC to soft
water - especially when operating in cold
weather. Without LLC, cooling performance
will decrease due to scale and rust in the
cooling 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 also. Do not
mix different types or brands of LLC or a
harmful sludge may form. Do not use hard
water. Water should be clean and free from
sludge or particles. 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 fresh
water cooling system. See Engine Coolant
Specifications on page 36. Excessive use of
antifreeze also lowers the cooling efficiency
of the engine. Be sure to use the mixing
ratios specified by the antifreeze
manufacturer for the temperature range.
Replace engine coolant periodically,
according to the maintenance schedule in
this Operation Manual. Remove scale from
the cooling system periodically by flushing
the system. Do not mix different brands of
antifreeze. Chemical reactions may make
the antifreeze useless and engine problems
may result.
Checking and Adding Coolant
3JH4E
0004556
(2)
(5)
(3)
(4)
(1)
(6)
Figure 11
1 – Coolant Tank (Heat Exchanger)
2 – Seawater Drain Cock
3 – Coolant Drain Cock (located behind
the V-belt cover) - 3JH4E Only
4 – Coolant Pump (Fresh Water)
5 – Seawater Drain from Seawater
Pump Cover
6 – Coolant Drain Cock
3JH4E
(1)
(2)
0004664
Figure 12
1 – Coolant Drain Cock
2 – Flywheel Housing
3 – Stop Solenoid
BEFORE YOU OPERATE
36 JH4 Series Operation Manual