NUT-FULL 6V7742 - Caterpillar

Replace the water temperature regulator before the water temperature regulator fails. Replacing the water temperature regulator is a recommended preventive maintenance practice. Replacing the water temperature regulator reduces the chances for unscheduled downtime.Note: Replace the coolant temperature regulators each time the coolant is replaced. Refer to this Operation and Maintenance Manual, "Fluid Recommendations (Coolant Recommendations)" for the correct interval.A water temperature regulator that fails in a partially opened position can cause overheating or overcooling of the engine.A water temperature regulator that fails in the closed position can cause excessive overheating. Excessive overheating could result in cracking of the cylinder head or piston seizure problems.A water temperature regulator that fails in the open position will cause the engine operating temperature to be too low during partial load operation. Low engine operating temperatures during partial loads could cause an excessive carbon buildup inside the cylinders. This excessive carbon buildup could result in an accelerated wear of the piston rings and wear of the cylinder liner.
Failure to replace your water temperature regulator on a regularly scheduled basis could cause severe engine damage.Caterpillar engines incorporate a shunt design cooling system and require operating the engine with a water temperature regulator installed.If the water temperature regulator is installed incorrectly, the engine may overheat, causing cylinder head damage. Ensure that the new water temperature regulator is installed in the original position. Ensure that the water temperature regulator vent hole is open.Do not use liquid gasket material on the gasket or cylinder head surface.
Location of the Water Temperature Regulators
Illustration 1 g02939580
Typical example
Two or four water temperature regulators may be located in the water line on the left side of the engine.
Illustration 2 g02939581
Typical example
Two or four water temperature regulators may be located under the expansion tank on the top of the engine.
Replacement Procedure
Refer to two articles in the Disassembly and Assembly Manual, "Water Temperature Regulators - Remove and Water Temperature Regulators - Install" for the replacement procedure of the water temperature regulator, or consult your Cat dealer.