Problem with set-screw on grey water valve

[Thurman]

I literally had to rebuild my drain plumbing system some time back as it was installed poorly at the factory. I have the "cable operated" grey and black water valves. After installing new valves I made sure that the cables were lined up well and were the proper length. The original ones were actually in a complete loop under the unit and enclosed with the under-belly sheet metal to boot. The black water valve has been so much better but the grey water valve has a problem with the set screw coming loose which allows the cable to come out again. I have changed the set screw for a new one with little teeth on the end, used a dab of lock-tite, and tightened, backed off, and re-tightened. Just this weekend we went camping and when I went to pulled the valve handle out---there was no resistance and no flow. The valve handle for the grey water just moves freely in and out. So, it's back under the unit again. Any suggestions as to how to make this set screw hold on better?

[OldCoot]

Originally Posted by Thurman

I literally had to rebuild my drain plumbing system some time back as it was installed poorly at the factory. I have the "cable operated" grey and black water valves. After installing new valves I made sure that the cables were lined up well and were the proper length. The original ones were actually in a complete loop under the unit and enclosed with the under-belly sheet metal to boot. The black water valve has been so much better but the grey water valve has a problem with the set screw coming loose which allows the cable to come out again. I have changed the set screw for a new one with little teeth on the end, used a dab of lock-tite, and tightened, backed off, and re-tightened. Just this weekend we went camping and when I went to pulled the valve handle out---there was no resistance and no flow. The valve handle for the grey water just moves freely in and out. So, it's back under the unit again. Any suggestions as to how to make this set screw hold on better?

Remove the set screw and mark the cable where it is supposed to seat on and pull the cable out and very carefully grind a small flat on it being careful not to grind thru' to the cable wire itself.

[Thurman]

Thanks for that reply "dunnnc". I was talking about this today with a couple of the contractors where I work and one had been through this very same experience. He also stated that he had pulled the bottom off of his trailer so many times he could do it while asleep now and has also given thought about leaving some panels off. He told me that he removed the valve giving him the same problem, took it into his shop then used a tap sized drill bit to drill straight into the threaded portion of the metal piece the cable fits into. He aligns the drill with the previously drilled hole which was tapped for the set screw. Now--he only drilled into the other side of this piece of metal a distance equal to the length of the point of the drill bit, sort of a "counter-sunk" type hole. Then when he tightens the set screw onto the cable he actually distorts the cable into the "counter-sunk" hole and it has held ever since. Not a bad idea really. Bet I'll have it done before sunset tomorrow (light rain this evening).