FRESH WATER TANK DESIGN

**DavePhelps** · May 4, 2016

We just picked up our Elite and the end of last March. Had a fine time meeting many of the crew at Oliver, Anita made us a pot of killer bean soup, and it was beautiful in Tennessee!

We took the long way home, taking 3 weeks and over 2500 miles to get back, with about 2/3 of that spent boondocking in various campgrounds. We absolutely love the trailer and it sheltered us well through freezing temps, snow, wind, and mountain squalls. One thing we began to notice while boondocking was that when the water level gets around 36% +/-, the water pump would cycle for a much longer period of time before shutting off (like a minute). As the level got down below 33% +/-, the pump would not shut off at all. After much head scratching, calls to Oliver, and checking for air leaks or any anomaly, I discovered the issue. The outlet tube that is at the "bottom" of the tank, is actually kind of high up. The tank itself (32.5 gallon) is 4.5" in overall height. The distance from the bottom of the tank to the top of the outlet tube is 1.5 inches! What this means is that as soon as the water level gets down to the top of that tube, the water pump will begin sucking air and loose prime. I was very careful to make sure my trailer was absolutely level while checking on this. This is a 33% loss of available water in the tank (10 gallons). The only way to get to it is to raise up the front of the trailer, but this has it's own negative issues (refrigerator, black tank/toilet, come to mind)

I would be curious to hear from you boondockers how you have dealt with this. Has anyone modified their tank or has this not been such a big issue to you? To me, this seems like a big design issue that Oliver needs to look at. The problem now is that the adapter/fitting that the pex tubing attaches to is glued to the exterior of the tank and there needs to be room for the gluing flange all around the adapter, this moves the tube up the tank wall. There has to be a solution out there somewhere. 10 gallons is a lot of water! I would never expect a 100% discharge, but only 66% is difficult to swallow, no pun intended there ;-)!

Thanks, and again, we love our Oliver and I would and will recommend it to anyone. Just want to make it even better, and learn more about this kind of travel (this is our first trailer).

Regards,

Dave

**routlaw** · May 4, 2016

Hi Dave

Interesting comment, thanks for starting. We've had our Oliver for just over a year also picked up on March 3rd 2015. We've encountered a similar issue albeit a bit different. First the measurement output of all of our tanks, fresh, gray, black are in 6% increments, interesting yours measures in 3% increments. That said we do not encounter the problem you bring up until we reach 13% though at 19% performance of the pump and pressure do start to diminish. We overcome this by adding more fresh water via the winterizing inlet and valves in bypass mode.

I haven't measured the distance from the bottom of the tank to the outlet tube, but 1.5" seems high based upon a visual inspection.

All that aside we discovered something interesting about the leveling of the Oliver on our last trip. You can't necessarily trust the bubble level at the tongue because its adjustable via the 3 set screws which are spring loaded from the back side of the bubble. During this recent trip I kept thinking the camper felt a bit tilted to one side and not level from front to back. So we made some crude adjustments until we returned home, it helped. Once home I got my Bosch laser level out mounted onto a tripod and set a beam across the belly band. Sure enough bumper to hitch was still out quiet a ways. Next step was to measure the back side for street to curb level and it was also off.

Effectively I leveled the camper using the belly band as the reference with the laser level, then adjusted the bubble to coincide with that adjustment. I would suggest you try something similar to determine that your bubble is accurate and if not make adjustments. However if we need to drain the fresh water tank completely the front needs to be raised by several degrees to accommodate this. We also do this while hitched when dumping gray water, makes it go much quicker.

**DavePhelps** · May 4, 2016

Hi Routlaw,

you are right in that our monitor also reads in 6% increments, so I should have said 36% and 30% respectively.

I never really trust those bubble vials. I tried adjusting it, but it was different every time! They're good to get in the ballpark, but I've been using my 2 foot level (Stabila) on the floor of the trailer. Figured that would be good for the tank position anyway. I was sent a pic of the tanks at the Oliver factory and they all look just like mine. The adapters are glued on by the tank manufacturer, not by Oliver, so I was told. Our tank monitor seems to be reading very accurately, at least by my measurements, crude as they may be. Remember that the 1.5" is to the top of the tube. If you're getting good pressure down to 19%, that's pretty good. I think what I will have to do is raise the front just a bit when we get down to 30%, or refill from water tanks carried in the TV like you. The tank manufacturer has a facility near where I live so I was thinking of stopping by to see if other fittings could be used or if something else could be done. On our trip home in March/April, it was early enough in the season that many campgrounds did not have the water turned on yet. This was in the Inter-mountain West. So we had to be careful with our water. No issues filling up at private RV parks and the like. We're on a learning curve here. But I was thinking if others are having a similar issue, that we could put our heads together and figure something out. I'll try to post a pic of my tank.

Dave

**DavePhelps** · May 4, 2016

My ruler is leaning a bit to the right. Space is tight down there! No way to lift the tank as a solution.....

Dave

**routlaw** · May 4, 2016

Good points. Regarding the bubble, you are correct in that it seems to change over time. For that matter if you push on the bubble as often as not it will not return to the exact same position even after adjusting. Early on I also tried the two foot level across the floor also but found ours was not exactly flat and even and so abandoned that solution. Plus it really is more efficient to have access to the bubble while adjusting the stabilizers.

Its interesting there is such a disparity between your fresh tank and ours regarding the volume of water inside though. Strange.

**Overland** · May 5, 2016

I see that the 1.5" measurement is to the outside of the tank. What is the thickness of the tank wall?

**Commanche** · May 5, 2016

We ave had problems with the bubble also, so we keep a small 6" level in the junk drawer and level off the counter between the sink and stove. I figure having the frying pan level is a good thing.

Stan

**DavePhelps** · May 5, 2016

Routlaw,

I'll have my wife in the trailer reading the level as I use the stabilizers. Man I love those things.

Overland,

The tank thickness I do not know and you raise a good point. I always assumed it wouldn't be more than 1/8 to 3/16 inches but I never could get that info. That would, of course affect my calculations by a small amount. Still hope to talk to the tank manufacturer. Even assuming a 1/4" tank thickness, there is a lot of water left in the tank that requires raising up the trailer to get to, which to me is not good practice, and is also just that much more extra weight I have to carry around.

Stan,

Yep, gotta have a level frying pan! I installed a lot of kitchens and making the stove perfectly level was a top priority!

Dave

**bugeyedriver** · May 5, 2016

Bubble "Stuff"

Be sure each screw is screwed in far enough so that it rests against the tension of the spring below it.

Use an actual LEVEL to level the trailer front to back and side to side. (I use the flat top of the stove as a reference)

Adjust the three screws to center the bubble. This adjustment should last several months before you may need to repeat.

Don't be surprised in very hot sun if the bubble has shrunk to the size of a pinhead ... It will grow again when it gets cooler.

**topgun2** · May 5, 2016

I too was having "troubles" with that small round bubble level. Once I got it set by using a four foot carpenter's level near the fridge on the inside I simply put two of those larger "stick-on" levels that I got from WalMart on the front and the side of the Ollie near the belly band. This way I use the little round bubble level to get things basically level and then refine this with the larger levels. Or, if I forgot my glasses, I simply use the larger stick-on guys.

Bill

**topgun2** · May 5, 2016

Sorry for the "bubble" hijack! Back to the original topic -

I just took a look yesterday at Twist's fresh water tank. I thought that I had emptied it prior to storage a month ago. Yes, I did the tilt thing but the reading still says 13% full. Going to have to work on that! Sure would be nice if the drain could just be shifted to the bottom. Even a small valve on the exterior of the hull would not bother me in that if it was done right it would still be at or even above the stringers.

Bill

**Overland** · May 5, 2016

Who makes the water tanks?

**DavePhelps** · May 5, 2016

http://www.epi-roto.com/plastic-water-tanks/

"Elkhart Plastics" is molded into my water tank, so I assume the above link is accurate. Although I cannot find my particular tank there (4.5 inches tall). I imagine Oliver has them custom made to fit their trailers.

Dave

**SeaDawg** · May 6, 2016

FWIW, and maybe not the same in the new bigger trailers, our tank will read accurate till 6 per cent, and not suck air. Also, our bubble has never been adjusted. Don't really care. If the trailer is comfortable for us, it's comfortable and ok for the refrigerator, according to Dometic, and so it goes. If we can't level completely because of a weird campsite, we hope to leave the headboard side of the trailer high for better sleeping, and level enough so the doors swing properly (not too much twist on the trailer.) Most of the time, we're within an inch or so of level, if I just walk into the trailer , feel the level, and walk out and readjust the jacks. The bubble always lies. Not a huge deal. (BTW, you can use a partial water bottle on its side as a level, if you think your level isn't correct. Old school carpenter trick.) We also have a small pencil level we carry with us.

To get that last few gallons, just as any other trailer, it can be necessary to jack one side and front a smidge to fill the inlet. We don't usually get to that point. As we normally wild camp, and carry fresh water in five gallon containers to supplement the trailer tank, I do the following to conserve water on most trips:

1. All drinking water is from the five gallon jugs, run into glasses or bottles. Coffee water is run into the tea kettle too.

2 I wash dishes with water heated in the tea kettle, from the jugs, in a dishpan. I can do dishes in a less than one quart tea kettle, by being careful. I also do dishes outside, most of the time, because I like it, and hate being inside when everyone else is having fun outside. I wipe food residue from dishes and silverware with the old napkins and paper plates after meals, save the dishes up, and do dishes once a day. Why waste the water, or the social time?

3. Rinsing glasses, brushing teeth, etc., is also usually done outside, with, you guessed it, the five gallon jugs carried in the truck. And the dog's water is from the jug, too.

So, basically, the trailer water is toilet flushing (minimal water), navy shower (if no other facility available), and handwashing. Not much. 32 gallons goes a long, long way if you're careful. With extra jugs, we can go weeks without having to go into town for extra water. We do have a soft bladder that we've used to refill the tanks. It's not a big deal, but an extra trip and time, and I'd rather go hiking. Or go to the farmers' market, cheese factory, or whatever...

Every time we come home from a camping trip, I have several thoughts (beyond, geez... all that laundry to do...) Our home is huge (it isn't), we waste a lot of water (we don't but certainly use more than we do when camping) and omg, we use a lot of energy... and we do, but we're careful about that at home, too, but still use so much more than when camping.

If we all lived at home as we do when we camp (or as I did as a kid on the farm...)....well, it might be a better world. Camping has helped me reconnect with what is really important.

Both our trailer (since 2008) and our home (since 2013) are solar powered. We conserve and collect water camping and at home. Precious resources. Precious world. Love the camping lifestyle, and love our Oliver, which makes it all easier.

Sherry

**DavePhelps** · May 7, 2016

Thanks for your reply Sherry. Leveling the trailer is not really the issue, although there have been some good pointers on this thread.

The problem for me is getting to "those last few gallons", as you say, which in my case is almost 1/3 the capacity of my tank! Now I'm completely into water conservation at home and camping and I employ many of the strategies you talk about. If I was getting full pressure down to 6% as you are, I'd be happy as can be. I would always expect to have to tip the trailer a bit to get that last bit of water, but not at 30% full. Perhaps this is just how it is and I'm expecting too much. I'm surprised others haven't had issues with this. I still want to visit the tank manufacturer to see what they can come up with so will report back with that before I put this to rest.

Dave

buckroe · May 7, 2016

Your not the only one with a water tank issue, We seem to be sucking air near 25-30 percent also. Please keep us posted on what you find out from the tank factory.

Kay and Kenny

**SeaDawg** · May 7, 2016

Dave, I hear you. That's a lot of water that you can't access, apparently, without taking the trailer out of level.

I wonder what the difference is in our older trailer. A few possibilities--perhaps our guage isn't accurate, and shows less water than what is truly left in the tank. Or, perhaps the tank is mounted differently , and more of the water can be pumped. I'd suspect the tanks are the same, or similar, as the capacities are the same in the specs.

Sherry

**DavePhelps** · May 7, 2016

For a different visual, here's a pic of the 32.5 gallon water tank at the Oliver factory. The outflow is on the right. The overall tank height is 4.5 inches or very close to that. I think a different fitting/adapter is in order, or perhaps a short ( 6" or so) siphon tube inside the tank that curved down to the bottom could help. Do you think a siphon tube would be problematic or potentially unsanitary over time? Seems like it would be just like the rest of the plumbing in the trailer and would be just as easy to sanitize if needed. Just thinking.....

Dave

**topgun2** · May 7, 2016

Dave,

Since one is pulling the water out of the tank anyway with the onboard pump, I think that your idea just might work. Emptying the tank for storage could have a similar arrangement but I'm not too sure if that last few gallons would siphon out with just gravity. However, if it didn't work, it would be fairly simple to just use the onboard pump to get it out. So, either way I think that it would be a bunch better than the way it is now.

Bill

buckroe · May 13, 2016

Dave, Thanks for the photo. Looks like you are on to something...

I was wondering if the tank in the photo was up side down? Could it be possible if one could remove the outflow adapter and modify it if a down-flow pickup in the tank? I haven't taken a look to see the outlet in the belly yet. Not sure where to start looking as we have a semi- permanent bed over the rear dinette.

**DavePhelps** · May 13, 2016

Buckroe,

unfortunately, there is no room to come out the bottom of the tank with an adapter, there is just no room. It has to come out the side, and therein lies the challenge of this design. Check this link out on a different forum, apparently this is not so uncommon an issue, and others have found ways to improve their system. http://www.crossroadsowners.com/forums/f14/fresh-water-tank-issue-8423.html

Of particular interest is the pic that Lloyd posted. (unfortunately, the link that was posted of 'Greg Paine' outlining this mod was not available to me to access, maybe someone else can get into it) It looks like there is a compression fitting through which one can insert a copper tube (maybe stainless would be better?). The tube could then be bent and inserted into the tank, and then the male end of the compression fitting screwed into the the stock adapter on the tank. Then the pex could be reattached to the other end of the copper/stainless tube. I need some time to research this fitting. Any plumbers out there? I've been buried lately and haven't had a chance to pursue this or get to the Elkhart factory, but am hoping next week to check this all out. I'll let everyone know when I get any new info together.

Hi Bill, yes, I think that this may just work with a little head scratching.

Dave

**DavePhelps** · May 13, 2016

Forgot to mention that the way my tank is oriented (and I'm sure all of the trailers), inlet and outlet facing the rear, and on the passenger side of the trailer, makes the adapter on the right in the above picture the outlet.

Dave

**topgun2** · May 31, 2016

Dave,

Anything new in your research of this issue? I'll be at the Mothership in very early July and if there is a "fix" it sure would be nice to get it done at that time.

Bill

**DavePhelps** · May 31, 2016

Bill,

I have been slow moving on this as life has been very busy. I have however learned of this idea using a brass compression fitting. Inside the stock fitting on the compression side is a stop so the copper tube won't go all the way through. What I did was to set the fitting up on my drill press and drill that stop out, and also continuing drilling out all the rest of the way through the fitting and out the 3/4" NPT side (the side that screws into the tank) with a 5/8" bit, which is the OD of 1/2" copper pipe. The brass drills very easily. I need to show this to my plummer to make sure there will be no leaking issues doing this. The beauty of the compression fitting idea (if it works) is that the bent siphon tube can be slipped in to the tank and allowed to rest at or near the bottom. The tube would not have to be straight up and down, but could just lay on the tank bottom at an angle, that way measuring the length is not so critical. Then the 3/4"NPT side of the fitting can be screwed in to the tank bung, the tube being still free to turn at this point. Then, when all looked good, the compression nut would be tightened down, locking everything in place. Then reattach the pex supply to the copper and you're good to go. What worries me is the very limited space under there to work and get wrenches in, etc. To do this at the factory would take no time at all! I really want a plummer to check this out before I commit. Trying to avoid the can of worms if I can!

I also tried using a nylon fitting with a pex tube glued into the NPT side with JB Weld plastic epoxy. But this test failed the glue test. No surprise as pex is impossible to glue so I have been told.

I will pursue this and post pics as soon as I can. Hope to talk to Tommy Staggs again this week to make sure the 1/2" copper tube will fit through the bung. Otherwise I'll have to step it down to 3/8" copper and use a comp. fitting configured for that size.

Dave

**KarenLukens** · July 27, 2017

I'm resurrecting your older thread Dave since now the problem has been resolved :)

Reed

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