COUPLER AS-HYDRAULIC 1901670 - 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.
Care must be taken to ensure that fluids are contained during performance of inspection, maintenance, testing, adjusting and repair of the product. Be prepared to collect the fluid with suitable containers before opening any compartment or disassembling any component containing fluids.Refer to Special Publication, NENG2500, "Caterpillar Tools and Shop Products Guide" for tools and supplies suitable to collect and contain fluids on Caterpillar products.Dispose of all fluids according to local regulations and mandates.
Keep all parts clean from contaminants.Contaminants may cause rapid wear and shortened component life.
Drain the coolant from the cooling system below the level of the water temperature regulator.
Illustration 1 g00992839
Remove bolts (2) and clip (3).
Remove pipe (1) and the gasket from the cylinder head.
Illustration 2 g00992840
Remove water temperature regulator (4).