So I started my coolant flush today around 1pm. Drained old coolant removed thermostat and flushed with water about 4 or 5 times. I then added the half gallon of restore topped of with water and drove around for about an hour and a half. Came back home and drained. Then started flushing with water. After what seemed like 10 or so flushes I'm still getting foam from the restore so I go ahead the remove the plug from the block and flush water through the system for about 10 to 15 minutes with the truck running. Water hose running enough to keep up with whats coming out. After this I done several more flushes still have foam coming out. All together I've flushed at least 20 times. So do I need to keep flushing until there is no foam coming out or can I move on to the restore plus.