WASHER-HARD 3V3308 - Caterpillar

Jacket Water System
Illustration 1 g00810876
(1) Bypass tube
(2) Water temperature regulator housing
(3) Tube to the front of the cylinder block
(4) Engine oil cooler
(5) Jacket water pump
(6) Inlet for the jacket water pump Jacket water pump (5) 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. gear groups that are high speed, medium speed, and low speed are used in order to maintain a proper speed of the pump's impeller. This will depend on the engine's rated speed. The coolant from the radiator or the heat exchanger enters inlet (6). The rotation of the impeller in the jacket water pump pushes the coolant through the system.Note: In applications that use a high water temperature, the engine oil cooler is in a separate circuit. A thermostatic valve controls the minimum engine oil temperature to the engine.The flow of the coolant is divided. Some of the coolant from the jacket water pump flows through tube (3) to the front of the cylinder block and the main distribution manifold for the water jacket of each cylinder. The remainder of the coolant flows through engine oil cooler (4) into the water jacket of the right rear cylinder. Coolant from both sources is mixed throughout the engine's water jacket.Note: For engines with two-stage aftercoolers, some of the coolant is diverted from the engine oil cooler in order to flow through the first stage of the aftercooler.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.
Illustration 2 g00810947
(2) Lower water temperature regulator housing
(3) Tube to the front of the cylinder block
(7) Tube from the cylinder head
(8) Water cooled exhaust manifold If the engine has a water cooled exhaust manifold, the coolant exits the cylinder heads through tubes (7) into water cooled exhaust manifold (8).
Illustration 3 g00812984
(2) Lower water temperature regulator housing
(3) Tube to the front of the cylinder block
(7a) Tube from the cylinder head
(8a) Water manifold If the engine has a dry exhaust manifold, the coolant exits the cylinder heads through tubes (7a) into water manifold (8a).
Illustration 4 g00810953
Top view of the water lines for the turbochargers and the exhaust bypass valve
(9) Turbocharger turbine housing
(10) Exhaust elbow
(11) Exhaust bypass valve
(12) Connection for a vent line Coolant flows through the exhaust manifold or the water manifold into lines for turbocharger turbine housing (9), exhaust elbow (10), and exhaust bypass valve (11). The coolant returns to the water cooled exhaust manifold or the water manifold.Connection (12) is for the venting of air from the low pressure side of the cooling system. The vent line from the connection must be straight and the vent line must have a slight upward