^^^ THIS. If you over concentrate the sca's you can cause continuing issues with the cooling system, multiple w/p failures, plugged oil cooler, radiator and aftercooler...if it has one, heater core, overheat issues.
It makes the inside of the engine a mess. I have seen the block coolant passages totally plugged by over concentration. If there is a "filter" on the engine, it ISN'T. It is a corrosion inhibitor. There are sca charge pellets/blocks inside the housing that release over time. This "filter" only needs service when the testing shows that the cooling system is in need of more sca. The only time I have seen liner pitting issues in these engines is when they are used in water trucks, when the coolant gets low, they just add nasty fire hydrant water, and trash trucks, because those companies have the worlds worst maintenance.
The mid stop linered engines, like the C in the 5 tons, honestly do not need a corrosion inhibitor. The way the liner is designed, it is spun steel, is supported mid level and barrel machined, doesn't have the same movement/resonance during the compression/firing cycle so it is way less susceptible to pitting/electrolysis that a cast/ top stop liner like the NHC and some of the CAT engines have. Cummins has even stopped installing corrosion inhibitors on the C and L series engines. They have not been installed since around 1998-99 when the CAPS C and L were introduced.
