Cooling System 47 Standard Antifreeze Testing General Coolant SCA level must be tested at least twice per year and whenever coolant loss occurs. For maximum coolant system efficiency, test the system every 25,000 to 30,000 miles (40,000 to 56,000 km), depending on the oil change interval, or every 1,000 hours or every 6 months (whichever comes first). Use liquid SCA and pre-charged coolant filters to maintain a 1.5 to 3.0 SCA units per gallon (0.4 to 0.8 units per liter) concentration in the coolant. W2003954 Depending on the make of antifreeze or premixed coolant, SCAs are added or have to be added to the system after replacement.
The SCA level will deplete over time so it is important that the SCA level is tested regularly and maintained. The Volvo pre-charged filter is designed to slowly release the SCA to help maintain the recommended level during operation. Note: Only change the filter after testing shows depleted SCA in the cooling system. DO NOT exceed the 3.0 units per gallon (0.8 units per liter) concentration. Excessive SCA concentration can form deposits on the higher temperature surfaces 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.
Excessive SCA concentration can also result in radiator tube blockage, overheating and/or accelerated water pump seal wear.