- Generator Set:
- C18 MARINE GS (S/N: CYN1-UP; MGS1-UP; CYG1-UP)
- Marine Engine:
- C18 MARINE (S/N: CKH1-UP; C1J1-UP)
Introduction
The problem that is identified below does not have a known permanent solution. Until a permanent solution is known, use the solution that is identified below.
Problem
Some C18 Marine frames of the heat exchangers leak around the thermostat housing on the rear frame of the heat exchanger. Metallurgical analysis confirms that the leaks are caused by excessive cavitation erosion to the aluminum frame. Analysis also indicates that poor properties of the coolant were a factor that contributed to these failures.
Solution
In order to repair a C18, replace the damaged frame with a new frame with the same part number. Drain the old coolant from the engine and replace the old coolant with Cat Extended Life Coolant (ELC). Refer to Operation and Maintenance Manual, SEBU6251, "Caterpillar Commercial Diesel Engine Fluids Recommendations " in order to switch from conventional coolant to ELC. Give special attention to the sections that refer to flushing the cooling system. If premixed ELC is not used, ensure that the water quality meets Caterpillar minimum acceptable water requirements that are outlined in Operation and Maintenance Manual, SEBU6251, "Caterpillar Commercial Diesel Engine Fluids Recommendations ". The Cat ELC does not require a traditional supplemental coolant additive. Use only ELC extender as outlined in Operation and Maintenance Manual, SEBU6251, "Caterpillar Commercial Diesel Engine Fluids Recommendations ". After switching to ELC, take a coolant sample and perform level 2 coolant analysis at 500 hours per the Operation and Maintenance Manual.
ELC offers superior protection against cavitation corrosion by providing a protective barrier on areas that are susceptible to cavitation. ELC reduces cavitation in similar areas of the cooling system. Examples are on cylinder liners and aluminum water pumps.
For additional information on coolant and engine cooling systems, purchase the publication, SEBD0518, "Know Your Cooling System" by calling 1-800-566-7782.