We're just back from a one month (4000+ mile) road trip with two of our grandkids. Halfway through the trip I noticed that the blackwater tank valve leaked. This happened after boondocking for the n...
A good way to tell which valve is leaking is to add a packet of Red Rit Fabric Dye to the gray water holding tank. First firmly seat the valve, add the dye, then run several gallons of water into the tank. Let sit for a while. You will see the red water if it's leaking. If no Red, then it's the Black tank valve leaking.