Loosing Water From The Fresh Water Tank

[HTWT]

Loosing Water From The Fresh Water Tank


Coley, maybe you can shed some more light on this…

Previously I asked the question about loosing water from the fresh water tank…I have to ask again. We like to dry camp and when doing so we have to have all the water we can carry. I fill up at home and while traveling water leaks out. In 4 hours of traveling we loose 2/3 of the tank.

What’s bringing this to the surface again is last weekend we camped at a state park in TX and before we left I put some water in the tank for the ride home, just for the use of the facilities if needed. As we were leaving the park I pulled into the dump station and found myself on a hill, nose up. As I emptied the gray water tanks all the fresh water drained out of the tank through the drains under the trailer.

This has nothing to do with walking away while filling the tanks or a “reverse vacuum” as Scott previously replied (see previous posts below). As far as traveling with as little water as possible…I don’t think we need to go there. I’m paying for the fuel and besides, the trailer does seem to ride better with a full water tank...maybe I have a center of gravity issue, I’ll work that one over the winter.


I honestly think this is a design problem, I have the dealer looking at it now, it’s in for winterization and some other little things.



Thanks in advance, HTWT


(Previous posts on the subject)
(Original post from me)
Loosing water from fresh water tank

Has anyone had any problems with water leaking out the fresh water tank drain tubes. I fill up at home and when we get to our destination we have only 2/3 (or less) of a tank left. At home when I fill, the water gauge shows full and the overflow runs, can’t put anymore in it. Additionally, it seems like the water pump is not as strong as it once was, water just seems to come out very slow. Shower works well after I changed the head.


(Scotts first reply)
One way that tanks empty...
What happens often with fresh water tanks as large as ours if that the owners hook up their water hose to fill the tank and then walk away and wait for the overflow tubes to start kicking out water to let them know their tank is full. While this may be more convenient than waiting and watching the monitor panel to monitor the water going into the tank, it often results in a "reverse vacuum". What happens is, the tank becomes full, and the water begins to flow out of the overflow tubes, but that overflow is not able to keep up with the amount of water coming into the tank from the hose. The result is, the tank begins to swell. (Note: there have actually been some who have caused their tank to swell so much that it caused damage to the coach).
Typically, a person stops the flow of water into the tank when they notice the overflow system kicking in - however - the tank may have already swollen up which means they can now have the reverse vacuum that I mentioned. It is very similar to cyphoning, in that the pressure now is going to go the other way, creating a vacuum, and emptying the water back out of the tank through the overflow lines. If a cyphone or reverse vacuum situation is created, it can actually keep going until the tank is 2/3rds to half way full before it stops. THAT is why some folks have problems filling their tanks up all the way.
The answer: ALWAYS be sure to keep an eye on your monitor panel when filling up your fresh water tanks. This will dramatically cut down your chances to create the reverse vacuum effect and loose the water that you were waiting so patiently to put in to the coach.

ST

(Scotts second reply)
Another Possibility
Concerning those who noticed some water coming out of the overflow tubes while traveling up a hill - even if you are not traveling with full tanks, when the coach is on an angle, yes, the water can get itself all to one end or the other and reach the top of tank and thus result is some water going out of the overflow tubes which operate through gravity.
One thing I will point out is that if at all possible, it is advisable to travel with very little water in your fresh water tank. This increases your cargo carrying capacity, your fuel mileage, and just makes the coach easier to tow down the road. Just a helpful hint.

ST

 

[davebennington]

We have had the same thing happen to us when we were out this past weekend. I filled the tank at home and when we got to the campground we were still dropping water from the overflow hose. Something is going on there.

Dave

 

[Scott]

Water Overflow

While having four overflow vents (one at each corner of the top of the tank) can make for water loss during travel - what you are describing is not typical.

When you say that the fresh water tank emptied when you pulled the gray tanks - that tells me that there is something up with your fresh water tank valve. We need to make sure it is closed all the way, and that it operates correctly - opening and closing off.
It obviously shouldn't empty out when the gray tank valves are opened.
We need to get your valves checked at a dealer to confirm whether or not they are operating correctly.

ST

 

[HTWT]

Loosing Fresh Water

Scott, I didn’t mean to imply that the fresh water tank emptied when I pulled the grey water valves, it emptied while on the hill, nose up. It didn’t have anything to do with the grey water valves, I just happened to be emptying the tanks at a dump station that was on a hill. The fresh water was draining from at least one (I didn’t look to see which ones were draining) of the three drains rear of the back tire as soon as the nose was tilted up hill. The same thing happens from starts from stop signs or traffic lights. Ironically, the dealer just called me back, I had him winterizing and checking out a few other things and he said exactly what you said, the drains are on top of the tank, water just comes out while the trailer is tilted or from starts after stops. This leaves me back to the design issue. I think, unless you have a lot of problem with this, I’ll cap the drains when I want to travel with a full water tank, else I’ll just loose water on the trip and fill up every morning at the campground before we leave. Just another step I guess. If you figure out what to do, as of now we plan on attending the rally in June, maybe we can do something there. Thanks, Rich

 

[Scott]

Fresh Water

Though we use large tanks in our coaches, they are relatively shallow, which allows for better weight distribution across the coach. With the overflow vents at the top of each corner of the tank, when you lifted the coach up on an angle, the back two vents began to let the water out. Short of installing a shut off valve on those overflow lines, I'm not sure what the solution is. I know we have to have the overflow vents/lines for code.
I will talk with engineering again to see what we can look at in the future to avoid the loss of water when a person is traveling. As far as parking on an incline, that will always cause the water to flow out one of the overflow vents, so there's not much to do about that without some sort of shut off - which I'm not sure is legal per code. I'll check into it.

ST

 

[BluegrassMan]

Losing Water

Hi All:

I have NOT experienced water Loss on our G. Canyon yet. I have gone DRY camping 3 times this summer.

THOUGH on our 98' Sea Breeze, the overflow tubes (2) were at my third axle UNDER the trailer. When I would chuck the tank full, the sloshing going down the road, would cause a cyphoning situation to take place. I placed vinyl caps over the hoses NO MORE 2/3 full tanks! When you arrive at your destination, you DO have to crawl under and slip them off so that the pump can pump.

 

[HTWT]

BluegrassMan, Thanks for the input, but why only 2/3 full?

 

[BigBlue]

Though we use large tanks in our coaches, they are relatively shallow, which allows for better weight distribution across the coach. With the overflow vents at the top of each corner of the tank, when you lifted the coach up on an angle, the back two vents began to let the water out. Short of installing a shut off valve on those overflow lines, I'm not sure what the solution is. I know we have to have the overflow vents/lines for code.
I will talk with engineering again to see what we can look at in the future to avoid the loss of water when a person is traveling. As far as parking on an incline, that will always cause the water to flow out one of the overflow vents, so there's not much to do about that without some sort of shut off - which I'm not sure is legal per code. I'll check into it.

ST

Scott
Is the black water tank shallow also? If so that might explain why I don't get the draining action I had from my old trailer. The pressure head isn't as high as my old one.

 

[BluegrassMan]

Losing Water

Hi All:
As I was stating, on my 98', I was losing approximately 1/3 tank of water on a 60 mile trip. If I had gone farther, I'm sure it would have been worse. I usually just put in about 20 gallon or so on a regular trip, then use the campground's water. REMEMBER ! Water is 8.83 pounds per gallon !

The plugs that I used were a flexible red vinyl just the right size to push on, and were tight enough not to fall off along the way.

 

[phranc]

We never have (with this railer)filled the fresh water tank.we put in just enough for travel so we haven't experienced any loss yet.That I know of ,that is..But say Bluegrassman,I wonder if one could extend the vents to the side of the unit and then put on a small brass shut off valve where it would be easier to reach ?

 

[BluegrassMan]

Syphoning out water ?

Hi All:

I guess that brass valves could be used, can't see why not. What is needed is just a was to stop the flow of air which causes the syphoning to start in the first place. I thought maybe the over flow hoses that stick out under the body could just be plugged, then NO suction can occour.

Just an Idea, Any thoughts out there ???

 

[BluegrassMan]

Shut off valves

Hi phranc:

The brass valves sound like a good idea. What is needed is to cut off the flow of air that is acting upon the tank, water sloshing, and air is moving at the same rate. STOP the air, syphoning stops. I was thinking that the hoses that come out under the body could be worked on, maybe valves there to cut off the air and or water.

Does this make sense to you...

 

[HTWT]

How I solved the problem

I went to Lowes and purchased plastic inserts with screw threads on one end, then bought the caps. Inserted the plastic fittings and screwed on the caps. I can now get to my destination with all the water I put into the tank, when I get there I take off the caps. I think the 1/4 turn valves previously mentioned is better, and much quicker. Thanks for the idea, I'll modify my fix. HTWT

 

[Paul & Nan]

We mostly go to state and county parks where there is no water hookups, so we need to carry water to last. Our guage for fresh water always reads 1/3 full after we have drained it to splutters. When we fill it, it reads 2/3 no matter what. We could last several days when we first got the rig, now it will only last a couple of days, and now we loose water when traveling, as mentioned above. It is a royal pain to run out of water in the middle of something when you have only been parked a couple of days and have been very careful.

Paul and Nan
2006 Bighorn 3500RL
2003 Silverado 2500 Duramax

 

[phranc]

found this thread regarding water loss

http://www.rv.net/forums/index.cfm/fuseaction/thread/tid/16837679.cfm

Seems water loss is other brands problem also

 

[dap]

Just an idea

I cannot see exactly the design everyone is talking about (waiting for delivery). But I think I have an pretty good perception of how things are laid out. Another idea since these are "vent tubes" (incorporated for the purpose of eqaulizing air pressure) would be to route the open ends to a location that is higher (much) than the top of tank rather than below the tank. This is a common practice in many types of tank designs. This way gravity would help solve the challenge rather than creating the issue. ...Just a thought.... trying to be helpful

 

[timk]

Dap
Great idea, but,....
a, How do you get to the tank? I think you would have to cut the underbelly apart.
b, I guess it wouldn't be to hard to run them up and out the wall somewhere if you could get to the tank.
Mine are just sticking down out of the underbelly just behind the axles. I would think that you would want them running uphill from the tank so that any water splashing would drain back into the tank. If you just hooked on to the lines under the coach and then ran up, you would create a water trap, much like under a sink. It makes my head hurt trying to picture if that would work. Might be an idea to consider sometime after a few beers, when your head is going to hurt anyway.
TimK

 

[phranc]

Seems like a decent production change for the factory.. Run the fresh water vent up to roof or under kitchen counter top ..I can see it now " Guaranteed not to lose fresh water ,unlike brand XXXXX"

 

[dap]

Hey guy's thanks for the kind words. I was looking at it from a production angle (a small change to the production line) since I understand that the belly of the trailer is completely sealed (one of the many features I've learned on this forum). I would also agree that you would want these run 100% uphill rather than creating a "water trap". I can't imagine that it would be that costly (clear plastic hose is cheap) or difficult to install it this way as it moved through the production line (but then again I have not taken a tour yet....so I really don't know whats involved). I don't think I would want to rig this up to a set of lines that allready drain below the tanks... sounds like water laying in low spots could sour or mold. The small brass valve idea sounds like the winner so far. Sound like I will have to figure out some solution for when my trailer is delivered. Many times I like to carry a tank of water with me (some of the camp ground water is nasty). I've often thought about adding one of those little seperate water facets to my sink for fresh water to cook with and for coffee that only ran off of the water pump. Another idea might be some little type of check valve designed so the check valve part (moving piece) was more of a little round ball that floated but was heavy enough and small enough to let air pass around it, but when it was hit with water it would float to the top and seal the ened of the line. I could probably draw it easier than I could describe it. This might be something we could throw together for just a few bucks..... just thoughts and ideas....

 

[timk]

Pictures of water tank

While tracking down a hydraulic leak, I spotted the offending tubes and tank. If you click on the link below you can see pictures taken from the rear of the rig, looking forward inside the frame above the underbelly. Sorry about the quality of pictures but it was a point and shoot thing.

Its a little hard to see in the pictures, but the water tank is only 7-10" tall and the vents are attached about 1-2" down from the top of the tank. So it doesn't take too much imagination to picture water splashing as your driving or if you park on a side hill, you could easily drain 20%-30% of your tank. I could only see one vent attachment, but I have read that there are four, so no matter which way the water is splashing some little bit is going out.

I like the idea of venting up. Good idea for the factory in the future. However it would be a job getting to the area to do a retrofit. At least in my 3400rl. If you had the major part of the underbelly off it wouldn't be to bad if you had a cabinet to hide the hoses in. But I do believe they should be vented to the outside so that when filling your tank, you don't fill your kitchen cabinets.

So having been to the tank and back, my thought is to just put a valve in the lines under the rig, (as someone has already suggested) and go get another margarita.

Link to pictures http://home.earthlink.net/~djshomeimprovement/data/water%20tank/

TimK