ROLLER GP-TRACK CARRIER 6Y1781 - Caterpillar

Illustration 1 g01193035
Schematic of cooling system (typical example)
(1) Water manifold
(2) Aftercooler
(3) Water temperature regulator housing
(4) Tube
(5) Cylinder head
(6) Cylinder block
(7) Engine oil cooler
(8) Tube
(9) Water pump
(10) Bypass tube Coolant goes into water pump (9) through an elbow. The elbow connects to the radiator or to the heat exchanger. The coolant flow is divided at the outlet of the water pump. Part of the coolant flow is sent to aftercooler (2) through tube (8). The remainder of the coolant goes through engine oil cooler (7).Coolant that is sent to the aftercooler goes through the aftercooler core. The coolant is sent by an elbow into a passage in cylinder block (6). The passage is near the center of the vee at the rear of the cylinder block. The coolant flows through the engine oil cooler into the water jacket of the cylinder block at the right rear cylinder. The cooler coolant and the hotter coolant are then mixed. The coolant goes to both sides of the cylinder block through distribution manifolds. The distribution manifolds are connected to the water jacket of all the cylinders. The main distribution manifold is located just above the main bearing oil gallery.The coolant flows upward through the water jackets. The coolant flows around the cylinder liners from the bottom to the top. The hottest temperature is near the top of 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 liner cooling. Coolant from the top of the liners goes into cylinder head (5). The cylinder head sends the coolant around the hottest parts. Coolant then goes to the top of the cylinder head. The coolant goes out through an elbow at each cylinder head and into water manifold (1) at each bank of cylinders. Coolant goes through the water manifold to temperature regulator housing (3).The water temperature regulator housing has an upper flow section and a lower flow section. The housing uses four temperature regulators. The sensing bulbs of the four temperature regulators are in the lower section of the housing. Before the regulators open, cold coolant is sent through bypass tube (10) back to the inlet of water pump (9). As the temperature of the coolant increases and the regulators start to open, the coolant flow in the bypass tube is restricted. Some coolant is sent through the outlets to the radiator or to the heat exchanger. The total system capacity will depend on the amount of coolant in the following components: cylinder block, radiator or the heat exchanger and the coolant lines.