Volvo D12, Operator'S Manual

Page: 49 / 214

Cooling System 45
Standard Antifreeze Testing
General
Coolant SCA level must be tested at least
twice per year and whenever coolant loss
occurs. For maximum coolant system effi-
ciency, test the system every 25,000 to
30,000 miles (40,000 to 56,000 km), de-
pending 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) con-
centration in the coolant.
W2001081
Depending on the make of antifreeze or
premixed coolant, SCAs are added or have
to be added to the system after replace-
ment. 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 rec-
ommended 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. Exces-
sive SCA concentration can also result in
radiator tube blockage, overheating and/or
accelerated water pump seal wear.
W2001082
Coolant filter