Open Cooling System; Full Closed Cooling System - ILMOR 2011 MV8 User Manual

Open Cooling System

Full Closed
Cooling System
The open cooling system
only. Whenever the boat is operated in brackish or salt water, particular care, without fail,
must be taken to flush the system with fresh water after every use. However, even if boating
in salt-free, apparently clean fresh water, flushing the cooling system following use is recom-
mended. This helps eliminate marine growth or fouling of the cooling system.
The full closed cooling system is the best application for boats operating in consistently
brackish or salt water. The system provides maximum protection for the engine against
corrosion, fouling and marine growth. As noted above, it is extremely important to keep
the system flushed after each use.
In a full closed system raw water is drawn into the boat by the raw water pump,
where it is distributed to the heat exchangers and then to the exhaust down-turn adapt-
ers before being returned to the body of water. The engine recirculation pump re-
circulates coolant through the engine and exhaust manifolds. Raw water never enters the
engine or exhaust manifolds.
2011 ILMOR MV8 Owner's Manual • Page 7
was designed primarily for fresh water use
In an open cooling system, raw water is drawn into the
boat by the raw water pump. (The intake is on the back of
the boat where it will be submerged and can draw water
continuously; the pump is located on the engine block.)
When the engine is cold, or the operating temperature
remains below 170 F. (76 C.), minimal water flows through
the engine and exhaust manifolds. All excess water will exit
into the exhaust manifold's down-turn adapters to cool the
marine rubber hoses for the wet exhaust system. Through
the exhaust, the water returns to the body of water.
When the engine is warm, with an operating tem-
perature greater than 170 F. (76 C.), the water from the
raw water pump feeds the engine recirculation pump.
The recirculation pump pushes water through the engine
block, cylinder heads and exhaust manifolds. When the
water mixes with the exhaust gases in the exhaust down-
turn adapters, it then returns to the body of water.