Waste valve question

[Gosman]

Question everyone
I have a 1972 Argosy and the waste valve... at the rear in side the bumper compartment when I push it in and lock it . It does not lock? why? and how can I fix it ?????? also I can only see or find one waste valve pull is this for both Black and Gray Water. I have looked every were and there is only one pull . Need some help and direction on how to proceed . HELP

[azflycaster]

The only locking on my valves is the clips that snap over the handle. These can be formed (bent) to hold the handle if they are not staying attached.

You only have one valve because you only have a black tank.