HOW-TO SECTION NOTICE: NOTE: In non-OAT systems, nitrite concentration of 5000 PPM or higher on a Series 60 engine suggests problematic additive over-concentration. This condition must be corrected by immediate draining and flushing of the cooling system. Refill the system with new fully formulated or pre-charged coolant. Check the nitrite concentration level at the next maintenance interval with a Power Trac 3–Way Test Strip. Failure to properly maintain coolant with SCA can result in damage to the cooling system and its related components. Conversely, over-concentration of SCA inhibitor can result in poor heat transfer, leading to engine damage.
Always maintain concentrations at recommended levels. Do not use traditional SCAs with OAT coolant. Additional SCA must be added to the coolant when it becomes depleted, as indicated by a nitrite concentration of 900 PPM or less. If the nitrite concentration is greater than 900 PPM, do not add additional SCA . If the nitrite concentration is above 3200 PPM, the system is over-inhibited and should be partially drained and filled with a 50/50 mix of water and EG or PG. SCA Test Procedures Detroit Diesel Power Trac 3–Way Coolant Test Strips should be used to measure nitrite and glycol concentrations. Part numbers are listed in Table 38.
Cavitation/corrosion is indicated on the strip by the level of nitrite concentration. Freeze/boil over protection is determined by glycol concentration. In this case the EG or PG should contain no inhibitors and should conform to ASTM D4985. This will dilute the over-concentrated inhibitors. 100 All information subject to change without notice. DDC-SVC-MAN-0039 Copyright © 2009 DETROIT DIESEL CORPORATION