Water Pump Not Getting All Water from Fresh Water Tank

Thomas Aaron · 08-18-2016, 12:21 PM

Hey, guys.

Now that I'm trying to do more boondocking, I'm found an issue with my FF 266-KIRB.

It has a 35 gallon holding tank, and twice now I've run it dry ... at least I THOUGHT I had run it dry.

As it turns out, the water pump will pull 23 gallons of water from the tank before it starts sounding like it is running dry.

However, I went out to the drain valve and literally measured (with a one-gallon jug) that there were 12 gallons of water left in the tank.

I guess my initial assumption is that the tube that goes from the pump to the fresh water tank isn't going all the way to the bottom of the tank.

The underside of my FF is completely sealed up, so I can't see the tank. I'm not sure if that can be fixed from under the sink, where the pump is located.

Thoughts?

Thanks guys.

Best Regards,
Tom Aaron

John_C · 08-18-2016, 06:33 PM

Hi Tom,
I couldn't say how or where your pump pick is located into the Fresh Water tank. Mine, however, enters the tank on one of the small sides (Street-side) at about an inch or so above the bottom of the tank; this will also hold a bit of water, although not as much as yours, due to my tank's smaller size...

profdant139 · 08-18-2016, 08:21 PM

I had the same problem, and I had my dealer move the pickup point to the lowest part of the tank. I now get almost all of my 30 gallons worth.

Thomas Aaron · 08-19-2016, 09:22 AM

Quote:

Originally Posted by John_C

Hi Tom,
I couldn't say how or where your pump pick is located into the Fresh Water tank. Mine, however, enters the tank on one of the small sides (Street-side) at about an inch or so above the bottom of the tank; this will also hold a bit of water, although not as much as yours, due to my tank's smaller size...

Thanks. My water tank is completely obscured, so this sounds like a warranty job. Thank you.

Thomas Aaron · 08-19-2016, 09:23 AM

Quote:

Originally Posted by profdant139

I had the same problem, and I had my dealer move the pickup point to the lowest part of the tank. I now get almost all of my 30 gallons worth.

Okay. Thank you. It is interesting to see that this issue seems to be somewhat common.

profdant139 · 08-19-2016, 12:12 PM

Tom, it is common with lots of trailers (and maybe other types of RVs). It is largely because the belly of the tank sags -- these things are plastic, not steel.

In addition to moving the pickup point, I added struts under the tank to hold up the sag. And I also put a shim under one lip of the tank, on top of a cross-member on the chassis, to tilt the tank so that the water runs to the side, rather than pooling in the middle.

runner421 · 08-19-2016, 02:00 PM

Ugh - yeah - seems like I fill my tank and seldom get what I consider to be "all" the water before my pump is blowing bubbles.
I hear the usual excuses, camper wasn't level when filling, camper should be higher on side with water fill. But I've always suspected the pick up hose wasn't placed in the optimum place.
Someday - I'll get motivated and remove the protective underskirt to get to all the tanks and such.
Until then, I curse you poorly engineered fresh water pickup.

**LJAZ** · 08-20-2016, 08:45 AM

There is supposed to be a small gap between the bottom of the tank and the pickup so that any sediment doesn't get picked up and clog the line. But high enough to lose a third of the tank volume is way too much.

Thomas Aaron · 08-23-2016, 12:20 PM

Quote:

Originally Posted by profdant139

Tom, it is common with lots of trailers (and maybe other types of RVs). It is largely because the belly of the tank sags -- these things are plastic, not steel.

In addition to moving the pickup point, I added struts under the tank to hold up the sag. And I also put a shim under one lip of the tank, on top of a cross-member on the chassis, to tilt the tank so that the water runs to the side, rather than pooling in the middle.

That would make a lot of sense. It is at my dealer for warranty work, and I pointed this out. Hopefully they will fix it, but maybe I should go in and ask them to look for this and find a way to support the bottom of the tank.

Good thoughts. Thank you.

John_C · 08-23-2016, 06:57 PM

Quote:

Originally Posted by Thomas Aaron

That would make a lot of sense. It is at my dealer for warranty work, and I pointed this out. Hopefully they will fix it, but maybe I should go in and ask them to look for this and find a way to support the bottom of the tank.

Good thoughts. Thank you.

Hi Tom,
I can be a Pain in the A$$ when it comes to dealers and mechanical shops, but I leave little to chance and can only tell you what I would do ... I would pay the dealer a visit, make sure he has written down everything I need checked/done, and then verify all work was done to my satisfaction before paying the bill and leaving... If some work will be covered, I would be there to look at the work before any panels, etc. are closed... but that's just me...

Good luck Tom and keep us posted...

hotdog · 08-25-2016, 09:40 AM

I discovered that problem in the middle of a shower. When I looked at the tank there was at least 1.5 inches of water in the tank when the pump stopped. The tank is listed at 25 gal (The actual tank dimensions- 46x28x5, plus belly bulge which makes it more like 28 gal). This equates to conservatively 7.5 gal (60 lbs) of useless water. Or about 25% of the tank.

Soooo, I replace the fitting with a dip tube to getting lower in the tank. Now I am leaving a gallon? in the tank.

Also, it was noted that the drain valve on the bottom does not completely empty the tank due to a large bulge in the bottom. As others have noted there is considerable sag in this tanks and they appear to need more support. Since this trailer is 5 years old I hope it is all sagged out.

PS I have a X-160 not a X-139 as seen on the axle label (in the picture). I too probably have an underrated axle for the trailer.

APD · 08-25-2016, 01:24 PM

Good deal! Sounds like you've gotten it solved. Did you buy the dip tube or make it yourself?

BTW: Measure the size of the axle tube. If it's 2 1/8" square it's a #9 which is #2200 max. 2 5/8" is a #10 and #4000 max. The #3500 brakes will fit both so hopefully your brakes are larger than the 7" which is standard on the #9 axles. (Info per Dexter Axle.)

twinster2 · 10-07-2016, 01:11 AM

I had a similar problem. My tank is 25 gallons and it was holding 10 gallons when the pump goes dry. I also added a pickup tub internal to the tank but kept the original fitting. Works well so far, but we will see if the tub stay put over then next year as we drive the potholed roads of Michigan. Below is a link to what I did.

http://www.funfinderclub.com/forums/...lons-3015.html