Water temperature regulators are used in each circuit in order to maintain correct operating temperatures. The water temperature regulators can control the minimum temperature to the inlet of the water pump or the minimum temperature at the outlet from the engine. This depends on the installation of the water temperature regulators.
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| Illustration 1 | g00485283 |
(1) Coolant outlet to the heat exchanger (jacket water) (2) Mixer housing (3) Coolant outlet to the heat exchanger (engine oil cooler and aftercooler circuit) (4) Aftercooler (5) Tube for the return of coolant from the turbocharger (6) Turbochargers (7) Supply line for coolant to the turbocharger (8) Water manifold (9) Engine oil coolers (10) Elbow (11) Jacket water pump (12) Inlet for coolant from the heat exchanger (jacket water) (13) Inlet for coolant from the heat exchanger (aftercooler and oil cooler) (14) Water pump for the aftercooler and oil cooler circuit (15) Bonnet for the engine oil cooler (16) Elbow | |
Jacket Water Cooling System
Water pump (11) (Illustration 1) is located on the right front side of the engine. The water pump has a gear that is driven by the lower right front gear group. Coolant from the expansion tank enters inlet (12). The rotation of the impeller in the water pump pushes the coolant to the side of the cylinder block through elbows (10) and (16) .
The coolant inside the cylinder block flows around the cylinder liners. The water jacket is smaller near the top of the cylinder liners. This shelf causes the coolant to flow faster for better cooling of the cylinder liner. The coolant is pumped up through water directors into the cylinder heads. The coolant flows through passages around the valves and the exhaust gases in the cylinder head.
The coolant flows out of the cylinder head through an elbow into water manifold (8). The coolant flows through the manifold to coolant outlet (1). The coolant exits the outlet and flows through a remote mounted water temperature regulator and the heat exchanger. The coolant then flows back to the expansion tank.
Coolant flows from the water jacket at the rear of the cylinder block through supply tubes (7) to turbochargers (6). Coolant from the turbochargers is returned to the cylinder block through tubes (7) .
A customer supplied vent line is required from the top of the turbochargers to the expansion tank. The vent line from the connection must be straight and the vent line must have a slight upward slope. The vent must not be obstructed.
Separate Circuit Cooling System
Water pump (14) (Illustration 1) is located on the left front side of the engine. The water pump has a gear that is driven by the lower left front gear group. Coolant from the heat exchanger enters inlet (13). The rotation of the impeller in the water pump pushes the coolant to engine oil cooler bonnet (15). Coolant flow is divided at the engine oil cooler bonnet. Part of the coolant flows to engine oil coolers (9). The remainder of the coolant flows to aftercooler (4). After the coolant flows through the aftercooler and the engine oil coolers, the coolant returns to the heat exchanger through mixer housing (2) and coolant outlet (3) .
A makeup line from the expansion tank to coolant inlet (13) helps maintain the coolant to the correct level.
A customer supplied vent line is required between the top of the housing for the engine oil coolers to the expansion tank. The vent line from the connection must be straight and the vent line must have a slight upward slope. The vent must not be obstructed.
Inlet Flow Control
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| Illustration 2 | g00829027 |
Schematic of a cooling system with inlet flow control (1) Orifices that are supplied by the factory (2) Orifices that are supplied by the factory or the customer (3) Vent lines (4) Orifices that are supplied by the customer (A) Turbocharger (B) Cylinder block and cylinder head (C) Jacket water pump (D) Water temperature regulator housing (jacket water) (E) Expansion tank (F) Heat exchanger (G) Engine oil cooler (H) Aftercooler (I) Mixer housing (J) Water pump for the separate circuit (K) Water temperature regulator housing (separate circuit) (L) Expansion tank (M) Heat exchanger (a) Port (b) Port (c) Port | |
The inlet flow control maintains a minimum inlet temperature to the water pump. The temperature regulators control coolant flow through the water temperature regulator housing by passing all of the coolant across the regulators. When the coolant temperature is below the rating of the water temperature regulators, the coolant flows through bypass port (b) across the temperature regulators and out of port (a). As the coolant temperature rises, the water temperature regulators open. The coolant from the heat exchanger flows through port (c) in order to mix with the remainder of the coolant as the coolant exits the water temperature regulator housing.
Outlet Flow Control
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| Illustration 3 | g00829000 |
Schematic of a cooling system with outlet flow control (1) Orifices that are supplied by the factory (2) Orifices that are supplied by the factory or the customer (3) Vent lines (A) Turbocharger (B) Cylinder block and cylinder head (C) Jacket water pump (D) Water temperature regulator housing (jacket water) (E) Expansion tank (F) Heat exchanger (G) Engine oil cooler (H) Aftercooler (I) Mixer housing (J) Water pump for the separate circuit (K) Water temperature regulator housing (separate circuit) (L) Expansion tank (M) Heat exchanger (a) Port (b) Port (c) Port | |
The outlet flow control maintains a minimum temperature at the outlet from the engine. The coolant flows from the engine's outlet across the temperature sensing bulbs in port (a). The temperature sensing bulbs determine the direction of flow through the water temperature regulator housing. When the coolant temperature is below the water temperature regulators' rated temperature, the coolant is bypassed around the external heat exchanger through port (b) to the inlet of the pump. As the coolant temperature increases, the water temperature regulators open. Some of the flow is diverted through port (c) to the heat exchanger.