MAINTENANCE 4. A corrosion inhibitor/conditioner is recommended to inhibit corosion in the cooling system for the following reasons: Improved compatibility with high silicate antifreezes minimizes hydro-gel formation, if over-concentration occurs. Provides engine protection in the following areas: - Solder corrosion/bloom - Copper corrosion/erosion/stress cracking - Oil fouling - Cylinder liner cavitation corrosion - Aluminum cavitation corrosion - Seal and gasket degradation Maintenance of Supplemental Coolant Additives Keeping the engine coolant properly inhibited will keep the engine and radiator free of rust, scale deposits and corrosion.
New machines are delivered with antifreeze protection. Service at a regular scheduled interval specified in 23 MAINTENANCE SCHEDULE CHART on page 3-25 , with a replacement coolant filter. Each time the coolant is drained and replaced, the coolant must be recharged with supplemental coolant additives. New coolant can be correctly charged with coolant additives by using a replacement coolant filter and/or concentrate. If coolant is added between drain intervals, additional coolant additives may be required. Coolant Testing for Conditioner Concentration When the cooling system is maintained as recommended, the conditioner concentration should be satisfactory.
The SCA concentration must not fall below 1.0 unit per 3.8 accurate method for testing chemical concentrations in coolant with mixed chemical compounds is a laboratory analysis. For this reason, the coolant inhibitor should be maintained as shown in 23 MAINTENANCE SCHEDULE CHART on page 3-25 . NOTICE: Inadequate concentration of the coolant additive can result in major corrosive damage to cooling system components. Over-concentration can cause gel formation that can cause restriction, plugging of passages, and overheating. Replenishing Coolant Conditioner Install a "precharge" coolant filter when the coolant is changed or a significant (more than 50 percent) coolant loss occurs.
Install a service coolant filter as specified in 23 MAINTENANCE SCHEDULE CHART on page 3-25 . When antifreeze is added, add coolant conditioner equal to 1.0 unit per 3.8 NOTICE: Mixing of DCA4 and other supplemental coolant additives is not recommended because there is currently no test kit available to measure concentration levels with mixed chemical solutions. Supplemental Coolant Additive Maintenance Guide Use supplemental coolant additives (corrosion inhibitors) to protect the engine cooling system from corrosion. Antifreeze alone does not provide enough corrosion protection for a heavy duty diesel engine.
Supplemental corrosion protection must be supplied through periodic additions of supplemental coolant additives to the coolant. To protect against corrosion, a new coolant charge must be brought up to 0.26 SCA unit per liter [one unit per U.S. gallon] of coolant (initial charge). Maintain the correct SCA concentration by changing the service coolant filter at each engine oil and filter change interval. Each time the coolant is drained and replaced, the coolant must be recharged with supplemental coolant additives. Use the appropriate replacement coolant filter listed in following tables.
The coolant mixture must be drained and replaced as defined under "General.” The amount of a replacement inhibitor is determined by the length of the service interval and the cooling system capacity. Refer to the DCA4 Unit Guide for the selection of the correct filter to replenish the SCA. WA450-3MC 3-14