Leakie Black and Grey water valves

[aframent]

I own a 2013 Keystone 5th Wheel 3582. Recently I have been having problems with my black and grey water valves leaking by.Especially the black. I installed an extra valve on the outside 3" line to solve the situation. I am noticing that the leaking is getting worse and am going to have to replace the valves that are in my underbelly. I am assuming that the black valve is 3". Does anyone know what size the grey valves. I bought another 3", but the more I think about it, the more I think it is a 2" or 1 1/2".
Please let me know if anyone has run into this problem. Going to replace both valves since I have to open my underbelly anyway.

The valves are opened and closed through cables that seem to be working fine.
Thanks for your input

[chuckster57]

Welcome to the forum!!!

No need to replace the entire valve, you just need new seals. The valve is a blade that slides between two rubber rings to seal off the tank.

Black is normally 3” and gray is normally 1 1/2”. Only trick is knowing brand of valve. Probably Valterra or Bristol.

You need the proper seal for the brand as they are NOT interchangeable. Just open up the underbelly and it should say on the valve.

If it’s Bristol then get Bristol seals.
If it’s Valterra then get the BladeX seals.

4 screws hold the valve assembly together.
Black valve is 7/16” nut and bolt
Gray will be 5/16” head on bolt and 3/8” nut.

Keep valve closed when installing new seals.