SEBU7899-05 73 Maintenance Section Cooling System Supplemental Coolant Additive (SCA) - Test/Add 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.
i04269112 Cooling System Supplemental Coolant Additive (SCA) - Test/Add (Systems Which are Filled with Conventional Coolant) 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. SMCS Code: 1352-045; 1395-081 This maintenance procedure is required for conventional coolants such as DEAC. Do not perform this maintenance for cooling systems that are filled with Cat Extended Life Coolant (Cat ELC) or Cat Extended Life Inhibitor (Cat ELI). NOTICE 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. Cooling system coolant additive contains alkali. To help prevent personal injury, avoid contact with the skin and eyes. Do not drink cooling system coolant additive. If the water temperature regulator is installed incor- rectly, the engine may overheat, causing cylinder head damage. Ensure that the new water temperature reg- ulator is installed in the original position. Ensure that the water temperature regulator vent hole is open.
NOTICE Excessive supplemental coolant additive concentra- tion can form deposits on the higher temperature sur- faces of the cooling system, reducing the engine's heat transfer characteristics. Reduced heat transfer could cause cracking of the cylinder head and other high temperature components. Do not use liquid gasket material on the gasket or cylinder head surface. NOTICE Care must be taken to ensure that fluids are contained during performance of inspection, maintenance, test- ing, adjusting, and repair of the product. Be prepared to collect the fluid with suitable containers before opening any compartment or disassembling any com- ponent containing fluids.
Excessive supplemental coolant additive concentra- tion could also result in blockage of the heat exchang- er, overheating, and/or accelerated wear of the water pump seal. Do not exceed the recommended amount of supple- mental coolant additive concentration. Refer to Special Publication, NENG2500, “Cat Dealer Service Tool Catalog” or refer to Special Publication, PECJ0003, “Cat Shop Supplies and Tools Catalog” for tools and supplies suitable to collect and contain fluids on Cat products. NOTICE Do NOT mix brands or types of SCA. Do NOT mix SCAs and extenders. Failure to follow the recommendations can result in shortened cooling system component life.
Dispose of all fluids according to local regulations and mandates. Note: If replacing only the water temperature regulator, only drain the coolant to a level that is below the water temperature regulator housing. Refer to two articles in the Disassembly and Assembly Manual, “Water Temperature Regulator - Remove and Water Temperature Regulator - Install” for the replacement procedure or consult your Cat dealer.