Saggy bottom and water tank that pump won't empty

[yvesm]

2011 Rockwood 2902DD
Well I am home until July 8 so I decided to fix a couple of things.1, the sagging underbelly material and 2, the water pump cannot empty the fresh water tank when its still 1/4 to 1/3 full. First the underbelly, I remover the corrugated plastic material that is forward and removed the pine (looked like scrap wood) that FR used as a way to fasten the underbelly to the frame. This wood was not treated and was starting to rot. As you can see by the images that the wood that FR used was not properly attached (few staples thru plastic) and the covering really sagged in the middle, by as much as 6''. I installed pressure treated stock (3/4''x 2 1/2'') am also made "T" beams to go across the trailer and 1 down the center, this made for a rigid but light structure to attach the covering to. I used GRK fasteners and stainless fender washers to attache the underbelly to the new wood. I have attached pictures that show the old setup and the new set up, no more sagging. As far as the water tank problem FR put the pump intake at about 2 1/2'' from the bottom of the tank, so when the water got low it would suck air (cavitate) until it could not pump anymore. So I plugged the hole and move the pump connection to the same place the drain is hooked up using a tee, the water tank has a low point here so now the pump can get all the water out!

Before and after

[yvesm]

Here are the images of the water tank mods

Before and after

[Herk7769]

Awesome idea.
I have no idea why they don't tee off in the drain line stock.

Any rep (or someone who "knows a rep") want to chime in about this?

[yvesm]

My previous RV the pump fed from the bottom

[LadyWindrider]

I am not a rep, nor do I know one. One reason for not using a "T" off the drain would be due to sediment. Leaving the suction line slightly high keeps the sediment out of the pump, and the water supply. Now a couple of inches seems really high, but there is no chance of any sediment getting in the pump at that point.

[Herk7769]

Windrider, I did actually think of that too. But then I figured with the screen filter on the inlet of the pump and that big honkin whole house filter they put in; sediment should be no problem.

[LadyWindrider]

Herk, you are correct when your trailer has those items. Ours doesn't, and most of the lower end stuff that I know of does not have the filters. On My Work and Play, there is just a plastic screen on the tank suction line. Might stop a rock the size of a "BB", but nothing smaller. Also the "whole house" filter is on the pressure side, and won't prevent pump damage if it sucked something in it. I know some of the pump inlets have the "fine screen" type filters right before the pump inlet to protect the pump.

[Herk7769]

Ah, I see your point. While I do have a fine screen inlet filter bowl on the pump itself, the whole house filter is on the pressure side so it filters incoming city water too. The pump only "sees" water from the fresh tank. I use my inline RV water filter when I fill the fresh water tank from an "unknown" (IE possible well or park) water source. While it won't take out esoteric micro-organisms or chemicals, it does a fine job with well pump silt.

[yvesm]

Like in a fuel tank for an airplane preflight, drain some fuel from the low point to get rid of junk in the bottom of the tank Being able to draw the water from the bottom of the tank alows me to travel with less water.

[LadyWindrider]

YVESM, you are correct, but not everyone on here knows anything about planes, or that they should drain a little water off in your modified set up. Nice pics, and post. When I got my camper home, I had to remove the suction line, and clean the screen, because all the plastic shavings where they cut the holes in the tank had clogged the screen and the water pump couldn't draw water through them. I also added some hard rubber strips under the metal bands holding the tanks up, as the tank could be bounced when empty. I added more strips on one end, casing the water to flow to the suction end of the tanks. I can now get all but about 2 gallons out by using the pump. (I used a big truck mud flap for the rubber strips, and used tie wraps to hold them in place. Cut the mudflap in to strips a little wider than the metal bands.) Nice mod, and pics.

[4Rasnicks]

Hello
Thank you for your post Yvesm! I have a 2011 8281SS with the exact same problem with the fresh water tank. After the pump starts sucking air i can open the drain valve and it will drain water for 20 minutes. I was going to tear into it this weekend. Now I know exaclty what I am going to do to remedy this issue! Thanks again.