INDICATOR (oil temperature) 1W0704 - Caterpillar

The engine has two cooling systems. The jacket water system cools the following components: engine oil cooler, cylinder block, cylinder heads, turbochargers, and aftercooler first stage. A separate system cools the aftercooler second stage.Water temperature regulators are used in each circuit to maintain correct operating temperatures.
Illustration 1 g06283077
G3516H and G3520H cooling system
Jacket Water System
Illustration 2 g06282725
G3516H and G3520H cooling system
(1) Inlet for the jacket water pump
(2) Jacket water pump
(3) Bypass tube
(4) Tube for the coolant supply to the aftercooler (first stage)
(5) Tube for the coolant supply to the cylinder block
(6) Oil cooler
(7) Tube for the coolant supply to the back right side of the cylinder block
(8) Tube for the coolant supply to the front right side of the cylinder block
(9) Tube from the cylinder head
(10) Coolant manifolds
(11) Lower water temperature regulator housing
(12) Water temperature regulator housing
(13) Outlet for coolant to radiator or heat exchanger
(14) Aftercooler (first stage)
Illustration 3 g06278865
(10) Coolant manifold
(13) Aftercooler (first stage)
(14) Coolant supply from cylinder block to turbocharger
(15) Turbocharger
(16) Coolant return from turbocharger to manifold
(17) Vent locationThe jacket water pump (2) is 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 a radiator or a heat exchanger enters the water pump inlet (1). The rotation of the impeller in the jacket water pump pushes the coolant through the system.The flow of the coolant is divided. Some of the coolant from the jacket water pump flows through a tube (4) to the first stage of the aftercooler (14). The remainder of the coolant flows through the engine oil cooler (6). The coolant leaves the aftercooler in tube (5) and merges with the coolant exiting the oil cooler (6) and supplies the front and rear of the cylinder block at (7) and (8).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 these items in the cylinder head: valves, valve seat inserts, spark plug adapter and exhaust outlets.The coolant exits the cylinder heads through tubes (8) into the coolant manifolds (10). Coolant flows through the line (14) to the turbocharger turbine housing (15). The coolant returns to the coolant manifold (10).Air is vented from the high points of the cooling system (17). 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.The coolant manifold directs the coolant to the water temperature regulator housing (11). The temperature regulator housing contains multiple temperature regulators. The temperature regulators control the direction of the coolant flow according to the coolant temperature.When the coolant achieves normal operating temperature, the water temperature regulators open and coolant flow is divided. Most of the coolant goes through a radiator or