the flapper boxes keep falling off and gettin gdragged byt he cable, I tried tightening the clamp but they still fall off, any one know how to prevent this?

Drive one sheet metal screw through each connection and tighten the clamps

Rich

If the clamp holding the flapper valve to the metal heater tube has been overtightened in the past the clamp can deform and reduce its ability to be tightened. If you remove the valve you can inspect the clamp and note if it is deformed. Then, using pliers, vice grips, vise, hammer, etc. you can reshape the clamp to its origanal shape to regain its clamping ability.

I think that's the ticket!