[Dakota773]

JSK

I have a 98 31 open. You are correct, the fresh water hook up in on the port side under the step. Attaching a garden hose will pressurize the system down stream of the freshwater pump. My freshwater pump is mounted on the mid-forward bulkhead (between engine bay and cabin) and easily accessible from the day hatch and probably on the stb side adjacent to the water tank. Hooking up the garden hose should put pressurized hose water through all fittings and thus flush them, including the water heater. Unfortunately not the freshwater tank. The only way to drain and flush that is to run water through the system (multiple times to really wash it out).

As for the water heater, mine is located in the cabin not the engine bay. It is in the lower storage bay below the power panel under the bench seat. I believe mine is configured with the overflow - pressure relief draining into the shower sump. As noted above, pressurizing with the hose does feed water through it.

Hope this helps.