SEAL ASSEM. 9U8538 - Caterpillar

Illustration 1 g00942607
Schematic of the coolant flow for the jacket water and for the separate circuit
Jacket Water System
Illustration 2 g00821761
(1) Tube for the coolant from the turbocharger and exhaust bypass valve to the water cooled exhaust manifold
(2) Water cooled exhaust manifold
(3) Bypass tube
(4) Water temperature regulator housing
(5) Outlet for the water temperature regulator housing
(6) Inlet of the jacket water pump
(7) Tube for the coolant to the turbocharger and to the exhaust bypass valve
(8) Engine oil cooler The jacket water pump is located on the right front side of the engine. The water pump has a gear that is driven by the front gear group. Coolant from the radiator or from the heat exchanger enters inlet (6). The rotation of the impeller in the jacket water pump pushes the coolant to engine oil cooler (8).The flow of coolant from the engine oil cooler is divided. Most of the coolant flows into the cylinder block.The remainder of the coolant flows through tube (7) in order to cool the turbocharger turbine housing and the exhaust bypass valve. Coolant from the turbocharger turbine housing and from the exhaust bypass valve flows through tube (1) to water cooled exhaust manifold (2).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 through the top deck of the cylinder block into the cylinder heads. The coolant flows through passages around the valves and around the exhaust gases in the cylinder head.The coolant exits the cylinder head through water cooled exhaust manifold (2). The water cooled exhaust manifold directs the coolant to water temperature regulator housing (4). The water temperature regulator controls the direction of the coolant flow according to the coolant temperature.When the coolant is cold, the water temperature regulator is closed. The coolant is routed through bypass tube (3) to the jacket water pump. The coolant continues to circulate through the engine.When the coolant achieves normal operating temperature, the water temperature regulators open and coolant flow is divided. Most of the coolant exits outlet (5) from the top of the water temperature regulator housings in order to be cooled by the radiator or by the heat exchanger. The remainder of the coolant flows through bypass tube (3) to the jacket water pump for recirculation. After the coolant is cooled by the radiator or by the heat exchanger, the coolant is routed to inlet (6) of the jacket water pump.Note: The water temperature regulators are necessary to maintain the correct engine temperature. If the water temperature regulators are not installed in the system, there is no mechanical control. Most of the coolant will take the path of least resistance through the bypass tube. This will cause the engine to overheat in hot weather. The small amount of coolant that goes through the radiator or through the heat exchanger in cold weather will not allow the