The majority of the silicate will be in the conventional coolant itself. Even low-silicate conventional coolants contain significant amounts of silicate. It is this silicate that drops out of solution. The SCA's will contain other things like phosphates, borates, and pH buffers. These can cause a scale build up in the coolant. After doing a good flush, very little contamination will occurr in the new coolant, and the HD ELC will continue to be very effective at inhibiting cavitation and corrosion. I would not recommend any type of chemical flush to "clean" the engine block any better.
