HANDLE AS 2007836 - Caterpillar

Jacket Water Aftercooling
Illustration 1 g06102104
(1) Active vents
(2) Water-cooled turbos
(3) Turbo water supply
(4) Turbo water return (Marine & Petro only)
(5) Radiator or heat exchanger
(6) Electronic Thermostat (ESTAT) for the jacket water cooling system
(7) Temperature Control Module (TCM)
(8) Jacket Water Aftercooler (JWAC) (front aftercooler core)
(9) Engine block
(10) Jacket water pump
(11) Engine oil coolerCoolant is pulled from radiator or heat exchanger (5) to water pump (10). From the water pump, coolant is sent through engine oil cooler (11). From the engine oil cooler, the coolant is sent to engine block (9). From the engine block, coolant is sent to ESTAT (6) and to the jacket water passage of the aftercooler (8). From the JWAC the coolant is sent to turbo water supply line (3) and to the water-cooled turbos (2). The coolant from the turbos is sent to the radiator through an active vent line (1) while the remainder is sent to JWAC (8) through turbo water return line (4) (In Marine & Petro Only). The ESTAT regulates the amount of coolant that flows through the radiator or heat exchanger to control engine temperature. The engine coolant that does not flow through the radiator is bypassed directly to the inlet of the jacket water pump.Coolant flows from the engine oil cooler into the water jacket at the front of the engine block. The coolant is directed toward the rear of the block through distribution manifolds. The distribution manifolds distribute the coolant to the water jacket for each cylinder. The coolant flows upward through the water jackets and around the cylinder liners. This area has the highest temperatures. As the coolant flows to the top of the cylinder liners, the coolant encounters a restriction due to smaller passages. The restriction causes the coolant flow to increase for improved cylinder liner cooling. Coolant flows from the top of the liners into passages that are cast into each of the cylinder heads. The coolant flows from the cylinder head back into the block and is returned to the front of the engine. As the coolant exits the front of the engine block, the coolant is directed through piping to the ESTAT and the after cooler core. Then the coolant is directed to the water-cooled turbo through the turbo water supply lines which removes the heat from turbos, from which it is routed to the radiator through the active vent lines. Due to the restriction of the piping and after cooler core, a larger portion of the coolant flows to the ESTAT. The return coolant from the core is piped into a tee at the ESTAT.
Illustration 2 g06104429
(12) Three-way valve
(13) Electronic Fluid Temperature Control (EFTC)
(14) Stepper motorThe ESTAT utilizes a 3-way valve (12) that is electronically controlled by EFTC (13) to distribute the flow of the engine coolant. Engine temperate is inlet sensed by the engine jacket water pump outlet temperature sensor and outlet regulated by the EFTC to the radiator / heat exchanger. The outlet flow of coolant is directed by a piston that rides on