Adding a drain to fresh water tank

[rwhmtnfolks]

My 2003 Palomino travel trailer has a typical side-mounted drain on the fresh water tank, but over the years the tank has bellied out and the drain is too high to get what appears to be 2-3 or more gallons of water. Is it possible to retrofit a drain to the bottom of the tank, or better, put a hose fitting on the bottom of the tank and run a hose with valve to the side of the trailer so it could be opened without crawling under the trailer. Thanks from the snowy mountains of Colorado.

[KyDan]

The problem is the material is so thin in the middle.
You can't drill and tap it and simply screw in a threaded plastic
fitting.
There are things called "bulkhead fittings" that are made to attach
pipes to tank walls or bottoms but you need inside access.
You would drill the proper size hole and put one part inside the
tank and the other part on the outside of the tank and screw
them together.
You can try googling for bulkhead fittings and see if you find one that
can be inserted from the outside but I'm not real hopeful.
You can try calling a plumbing supply shop or even contact a tank
manufacturer.
Look online for RV water tanks and get the name of the maker
and then google them to find their address and phone number.

Maybe someone else can come up with a better idea.
Good luck!

[rwhmtnfolks]

Dan, I hadn't heard of bulkhead fittings before, but I think you've provided me the answer. I've found a 1/2" fitting that I think I can fish through the freshwater inlet and to that attach an elbow, piping and spigot. The fitting is light-duty, but if I support the piping from it with strapping and make sure the piping is not bouncing around and stressing it, I think it'll work just fine. Thanks for your help. Wayne

[GSF63]

A fix that I used a few years ago was to add more support strips under the tank. I doubled the number of supports and that removed the low spots.

[cheese53073]

I would consider shimming or re-supporting the tank also. that way if it doesn't work you will still have a useable tank. with the added drain fitting you still will not get a full drain as there will be a lip or nut inside the tank.

[rwhmtnfolks]

Thanks for your and Gary's suggestions. You're right that a bulkhead fitting would leave some water in the tank, but far less than I have today. Adding another support or replacing the current support is an option I should consider, though it's considerably more costly than a new drain. Then again, a ruined tank is pretty costly also. So I have some cogitating to do.