VALVE AS- 3728434 - Caterpillar

Removal Procedure
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 cooling system pressure cap slowly to relieve pressure only when engine is stopped and cooling system pressure cap is cool enough to touch with your bare hand.Do not attempt to tighten hose connections when the coolant is hot, the hose can come off causing burns.Cooling System Coolant Additive contains alkali. Avoid contact with skin and eyes.
Drain the coolant from the cooling system into a suitable container for storage or disposal. Coolant should be drained until the coolant is below the level of the water temperature regulator housing. Refer to Operation and Maintenance Manual, "Cooling System Coolant - Change".
Illustration 1 g03296797
Remove bolts (1) and cover (2) .
Illustration 2 g03296816
Remove O-ring (3) and water temperature regulator (4) .Installation Procedure
Install water temperature regulator (4) in the reverse order of removal.
Fill the cooling system. Refer to Operation and Maintenance Manual, "Cooling System Coolant - Change".