GEAR 3722009 - Caterpillar

At operating temperature, the engine cooling system is hot and under pressure. Steam can cause personal injury. Check the coolant level only after the engine has been stopped and the fill cap on the radiator is cool enough to touch with your bare hand. Remove the fill cap slowly to relieve pressure. Cooling system conditioner contains alkali. Avoid contact with skin and eyes to prevent personal injury.
1. Drain the coolant until the level is below the water temperature regulator. Be sure to drain the coolant into a suitable container. The total capacity of the cooling system is 42 liters (11 U.S. gal).2. Disconnect upper radiator hose (1) and water line (5).3. Remove four bolts and washers (2), two wiring harness clips (3), and regulator housing assembly (4) with its gasket. Remove the water temperature regulator from regulator housing assembly (4). The following steps are for the installation of the water temperature regulator.4. Lubricate the lip of the internal seal with glycerin prior to assembly and installation.5. Insert the water temperature regulator into regulator housing assembly (4).6. Inspect the gasket for wear or damage, and replace if necessary. Place regulator housing assembly (4) and its gasket into position on the engine.7. Install four bolts and washers (2), and secure two wiring harness clips (3) and the regulator housing assembly (4).8. Connect upper radiator hose (1) and water line (5).9. Fill the cooling system to the correct level. See the topic "Lubricant Viscosities & Refill Capacities" in the Operation & Maintenance Manual.