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The Expansion Tank Sometimes attached to the heat exchanger itself, sometimes mounted remotely, this tank is a very important part of a closed cooling system. As the engines water coolant gets hot it will expand, increasing in volume. This water needs somewhere to go and the expansion tank is a tank that provides room for this hot water to expaned into.
We carry a couple stock replacement expansion tanks here. The Half System Engine Block Only The half closed cooling system is designed to circulate cooling water through the block only. As shown in the diagram below, raw water is picked up through the drive pickup or through a hull mounted pickup, if present it will pass through a sea strainer to clean debris out of the water.
From there it will pass through the raw water pump. The raw water will be used with your Engine Oil and Power Steering Coolers as they will not be part of the closed circulating system.
From Here the raw water will be passed into the heat exchanger tank and be pumped through many small tubes where it will exchange heat from the circulating systems water. The raw water then exits the heat exchanger to go through the manifold, into the riser and then exit the boat.
As for the circulating water in closed cooling system, cool water will enter the engine through the circulating pump and circulate through the engine. Hot water will exit at the water outlet on top of the manifold and head to the heat exchanger to exchange the heat it's carrying with the raw water.
After the exchange the cool circulating water exits the heat exchanger and returns to circulating pump to begin another loop.
See below for a diagram of the half system operation: The raw water then exits the heat exchanger to go directly into the risers and then exit the boat. The exhaust manifold and riser will be blocked off, so no water will transfer between them.
The water will heat up in the engine and the warm water will exit at the water outlet on top of the manifold and head to the manifolds. After circulating through the manifolds, the hot water will head to the heat exchanger to exchange the heat it's carrying with the raw water.
See below for a diagram of the full system operation:Mercruiser Freshwater Cooling Kits, find direct replacement water pumps, thermostats, impellers, heat exchangers and other Mercruiser boat parts.
Free Shipping on . Raw Water Cooling – sample drawings All drawings taken from Marine Diesel Basics books – click on drawings to learn more about each topic Inspect Rubber Impeller Cooling Pie Chart Cleaning Pump Cover Topics covered in chapter 4 21 drawings + text Maintenance – Raw Water Cooling Main Concerns Task List Indirect Cooling (Fresh Water Cooled) Direct Cooling Keel Cooling 1 Clean Thruhull of feelthefish.com · Marine Engine Application and Installation Guide Fresh Water Cooling locations are shown in Figure 1 for a combined system and Figure 6 for a separate circuit system.
Temperature Regulation Inlet control temperature regulators are used on the jacket water feelthefish.com – fresh water cooled (indirect cooling) where the engine has its own closed loop cooling system similar to that of a motor car. The temperature of the engine coolant is reduced by being passed through a heat exchanger which is itself cooled by a supply of continuously pumped sea feelthefish.com://feelthefish.com Figure 1.
District cooling system components. Sewage treatment plant (STP) treated water is used as make up water in cooling towers; this reduces the requirement of fresh water. Figure 10 shows the cooling towers. Figure Cooling feelthefish.com://feelthefish.com Fresh Water Cooling System Introduction Although there is an abundance of free sea water available, marine diesel engines do not use it directly to keep the hottest parts of the engine cool.
This is because of the corrosion which would be caused in the cooling water.