SENSOR GP- 5401590 - Caterpillar

Make sure you read and understand the information in the topics Safety and Cooling System Specifications for all information pertaining to water, antifreeze and supplemental coolant additive requirements before you proceed with maintenance of the cooling system.
To Drain the Cooling System
The filler cap is located beneath the access cover on top of the hood, forward of the engine exhaust tube.
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Put the machine on a hard level surface, set the parking brake, and turn off the engine.
Personal injury can result from hot coolant, steam and alkali.At operating temperature, engine coolant is hot and under pressure. The radiator and all lines to heaters or the engine contain hot coolant or steam. Any contact can cause severe burns.Remove filler cap slowly to relieve pressure only when engine is stopped and radiator cap is cool enough to touch with your bare hand.Cooling System Conditioner contains alkali. Avoid contact with skin and eyes.
Slowly loosen filler cap (1) in order to relieve system pressure. Remove the filler cap.
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Remove access cover (2) for the coolant drain. The cover is located on the right side near the front of the bottom engine guard.
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Coolant drain valve viewed through access hole in bottom engine guard
Remove plug (3) from the drain valve. Install a 12.7 mm (.5 inch) drain pipe into the drain valve. The pipe must have 1/2 - 14 NPTF threads. Clamp a hose to the pipe in order to direct the coolant into a suitable container.
Open drain valve (4). Allow the coolant to drain into a suitable container.
Flush the system with water. Flush the system until the draining water is clear. Note: If the cooling system is already using ELC, cleaning agents are not required at the specified coolant change interval. Cleaning agents are only required if the system has been contaminated by the addition of some other type of coolant or by cooling system damage. Clean water is the only cleaning agent that is required when ELC is drained from the cooling system.Note: If you change to ELC from another type of coolant, use a Caterpillar cleaning agent to flush the cooling system. After you drain the cooling system, thoroughly flush the cooling system with clean water. All of the cleaning agent must be removed from the cooling system. Refer to the Topic “Cat Extended Life Coolant (ELC)” in Operation and Maintenance Manual, SEBU6250.
Close drain valve (4), then remove the drain pipe if previously installed. Install plug (3).
Replace access cover (2).
Add the ELC solution. See the following topics in this publication:
Cooling System Specifications
Capacities (Refill) Note: Caterpillar antifreeze contains additives. If you are using Caterpillar antifreeze, do not add the supplemental coolant additive at this time. Also, do not change the supplemental coolant additive element at this time.
After the cooling system has been filled, perform the following procedures during initial start-up:
Start the engine without the filler cap.
Run the engine at low idle for 10 minutes.
Then, increase the engine speed to a high idle until the thermostat is open and the coolant level is