HARNESS AS-SENSOR 4549730 - Caterpillar

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.Do not attempt to tighten hose connections when the coolant is hot, the hose can come off causing burns.Cooling System Conditioner 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.
The water temperature regulator is located on the top front of the engine.Replace the water temperature regulator on a regular basis in order to reduce the chance of unscheduled downtime and of problems with the cooling system. The water temperature regulator should also be replaced after the cooling system has been cleaned.Replace the water temperature regulator while the cooling system is completely drained or while the cooling system coolant is drained to a level that is below the water temperature regulator housing.
Failure to replace the engine's water temperature regulator on a regularly scheduled basis could cause severe engine damage.
Note: If you are only replacing the water temperature regulator, drain the cooling system coolant to a level that is below the water temperature regulator housing.
Illustration 1 g00720250
Loosen hose clamp (1).
Remove hose (2) from connector assembly (3).
Remove bolts (4) and washers (5) from the connector assembly.
Remove the water temperature regulator from the water temperature regulator housing (6). Check the gasket for wear or damage. If necessary, replace the gasket.
The water temperature regulators may be reused if the water temperature regulators are within test specifications, are not damaged, and do not have excessive buildup of deposits.
Since Caterpillar engines incorporate a shunt design cooling system, it is mandatory to always operate the engine with a water temperature regulator.Depending on load, failure to operate with a water temperature regulator could result in either an overheating or an overcooling condition.
If the water temperature regulator is installed incorrectly, it will cause the engine to overheat.
Install a new water temperature regulator into water temperature regulator housing (6).
Install connector assembly (3).
Install washers (5) and bolts (4) and tighten.
Install hose (2). Tighten hose clamp (1).
Refill the cooling system. Refer to Operation and Maintenance Manual, "Refill Capacities" and Operation and Maintenance Manual, SEBU6250, "Caterpillar Machine Fluids Recommendations".