Radiator Cooling System
In normal operation, the water pump (10) sends the coolant from the radiator (5) to the engine oil cooler (7). The coolant then flows to the cylinder block. The coolant then flows through the cylinder block to both of the cylinder heads. The coolant then flows to the temperature regulator housings (3). When the temperature regulators are open, most of the coolant flows through the outlet (4) to the top of the radiator (5) (one on each side of the engine front). The coolant becomes cooler as the coolant moves through the radiator. When the coolant goes to the bottom of the radiator, the coolant goes through the water pump inlet (11).
 | |
| Illustration 1 | g01246681 |
An example of a radiator cooling system (1) Turbochargers (2) Aftercooler (3) Temperature regulator housings (4) The outlet from the temperature regulator housing to the radiator top (one on each side of the engine front) (5) Radiator (6) The outlet of the bonnet of the oil cooler (7) Engine oil cooler (8) Line to the aftercooler (9) Inlet bonnet of the oil cooler (10) Water pump (11) The water pump inlet from the bottom of the radiator (12) Radiator bypass lines | |
 | |
| Illustration 2 | g01246683 |
Cooling system components (1) Turbocharger (2) Aftercooler (3) Temperature regulator housing (4) Outlet to the radiator top (6) The outlet of the bonnet of the oil cooler (7) Engine oil cooler (8) Line to the aftercooler (9) Inlet bonnet of the oil cooler (10) Water pump (11) The water pump inlet from the bottom of the radiator (12) Radiator bypass lines | |
Note: The water temperature regulator is an important part of the cooling system. The water temperature regulator divides the coolant flow between the radiator (5) and the bypass lines (12). This will maintain the correct temperature. There is no mechanical control if the water temperature regulator is not installed in the system. The coolant will take the path of least resistance and the coolant will go through the bypass. This will cause the engine to overheat in hot weather. During cold weather, any coolant that goes through the radiator is too much coolant. The engine will not reach normal operating temperatures.
The water temperature regulator is closed when the engine is cold. The coolant flows through the temperature regulator housing (3) through the radiator bypass lines (12) and back to the water pump (10) .
Engines that are equipped with an aftercooler will divide the coolant flow. Part of the coolant will flow to the engine oil cooler and part of the coolant will flow through line (8) to the aftercooler. From the aftercooler, the coolant flows through the block, through the heads and back to the regulator.
If the engine is not equipped with an aftercooler, line (8) becomes an oil cooler bypass line. This line will connect to the outlet of the oil cooler bonnet (6). Part of the coolant will flow through the engine oil cooler (7) and part of the coolant will flow through the bypass line (8). The coolant will flow from the outlet of the oil cooler bonnet (6) through the cylinder block. The coolant then flows from the cylinder block through the cylinder heads.
On some engine applications, water cooled manifolds and a water cooled turbocharger is used. The coolant is taken from the rear oil cooler bonnet (6) and flows to the bottom of the water cooled turbocharger. The coolant flows from the top of the turbocharger. Part of the coolant flows through a line back to the water pump. The remainder of the coolant flows through the manifolds back to the regulators.
Coolant Conditioner
Some conditions of operation can cause pitting on the outer surface of the cylinder liners and on the cylinder block surface next to the liners. This pitting is caused by corrosion or by cavitation erosion. A corrosion inhibitor is a chemical that provides a reduction in pitting. The addition of a corrosion inhibitor can keep this type of damage to a minimum.
The coolant conditioner element is a spin-on element that is similar to a fuel filter and to oil filter elements. The coolant conditioner element attaches to the coolant conditioner base that is mounted on the engine or mounted on a remote location. Coolant flows through lines from the water pump to the base and back to the block. There is a constant flow of coolant through the element.
The element has a specific amount of inhibitor for acceptable cooling system protection. As the coolant flows through the element, the corrosion inhibitor goes into the solution. The corrosion inhibitor is a dry solution, so the inhibitor dissolves. The corrosion inhibitor then mixes to the correct concentration. Two basic types of elements are used for the cooling system. The two elements are the PRECHARGE elements and the MAINTENANCE elements. Each type of element has a specific use. The elements must be used correctly in order to get the necessary concentration for cooling system protection. The elements also contain a filter. The elements should remain in the system after the conditioner material is dissolved.
The PRECHARGE element contains more than the normal amount of inhibitor. The precharge element is used when a system is first filled with new coolant. This element must add enough inhibitor in order to bring the complete cooling system up to the correct concentration.
The MAINTENANCE elements have a normal amount of inhibitor. The maintenance elements are installed at the first change interval. A sufficient amount of inhibitor is provided by the maintenance elements in order to maintain the corrosion protection at an acceptable level. After the first change interval, only maintenance elements are installed. In order to provide the cooling system with protection, maintenance elements are installed at specific intervals.