We used shout detergent to wash the radiators when oil was mixed in the engines, today I wash the black tank with dish washer detergent and a wand, I fill the tank half way and use the spray wand, then of course I have a straight shot.
Once I have made enough suds I let the whole mess sit for a while and then dump while the spray wand is the running, it is amazing how much sticks to the walls.
My sensors quit working years ago and they never read correct, the only one that reads correct is the propane sensor.
navegator
