Dreaded water heater check valve repair....
Just completed the check valve repair. Hot water flow had dropped to a trickle so I had to dive in. On our 37B Adventurer the WH was behind the right front wheel. The access was through the inside wall behind the water pump. It was only possible to reach it with one hand as I didn't have any skinny grand kids available. I removed the water pump and the slide cover that helped some. I then used my Harbor Frieght Multi-tool saw to enlarge the plywood wall the pump is mounted to. I marked the blade at 3/4" so as not to get into the gas line behind the wall. It is not too hard but a 1" deep socket for the check valve is a life saver. The check valve was very tight so get ready.
Sure enough the plastic poppet and spring had shifted so I pushed them out as I blow out the system to winterize and do not require the check valve. I reinstalled the valve body with some teflon tape and it's good to go.
If yours hasn't been a problem I would recommend getting a 1" deep socket because every time I mention this problem there are several people that have had the issue.
2004 37B Adventurer, 8.1 WH, Ultrapower, DIY CAI, Henderson Track Bar, Tru Center, Koni FSD's, Roadmaster Even Brake, Scan Guage II, 180 Thermostat,