PIN 5000269 - 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 the cooling system pressure cap only when the engine is stopped and is cool enough to touch with your bare hand. Lift the lever on the pressure cap to relieve the cooling system pressure before removing the pressure cap.Do not attempt to tighten hose connections when the coolant is hot because the hose can come off which could result in burns.Cooling System Coolant Additive contains alkali. Avoid contact with skin and eyes.
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 be replaced after the cooling system has been cleaned. Replace the water temperature regulator while the cooling system is drained, or at a level where the water 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 a water temperature regulator, drain the cooling system coolant to a level that is below the water temperature regulator housing.
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, "Dealer Service Tool Catalog" for tools and supplies suitable to collect and contain fluids on Cat® products.Dispose of all fluids according to local regulations and mandates.
Illustration 1 g02749776
Remove water temperature regulator housing.
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Remove the gasket, the water temperature regulators, and the seal from the water temperature regulator housing.
Former water temperature regulators may be used, if they meet the test specifications and are not damaged or have excessive buildup or 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 seal in the water temperature regulator housing. Install new water temperature regulators and a new gasket. Install the water temperature regulator housing and the hose.
Refill the cooling system. Reference: For all cooling system requirements, refer to the Operation and Maintenance Manual, SEBU6250, "Caterpillar Machine Fluids Recommendations".Reference: For information on the cooling system capacity, refer to the Operation and Maintenance Manual, "Lubricant Viscosities and Refill Capacities" for the machine that is being serviced.