Fresh water - where did it all go?

_nelsonc · 07-07-2013, 11:30 AM

Recently spent 4 days dry camping in a local state park. Full fresh water tank lasted all four days. Filled up again and took off for Skyline Drive. By the time we got to the Lewis mountain Campground the tank was down to 1/3. The entire trip was spent on US50 and US33 so we are talking a roller coaster ride. Is it possible that the water sloshed out the overflow as I went up and down the 7-10% grades I was driving on?

I didn't notice the water was low till we stopped to take some pictures and I heard the water pump running when there wasn't anything on. There was a higher than expected amount of water in the rear black tank. But with the 66 gallon fresh tank and 45 gallon black tank, the 2/3 full black tank does not equal the 44 gallons missing out of the fresh tank.

This was on a 2013 Coachmen Mirada 35DL. Thoughts appreciated!

garbonz · 07-07-2013, 11:45 AM

Don't run down the road with the pressure water pump switch on.

_nelsonc · 07-07-2013, 11:49 AM

Quote:

Originally Posted by garbonz

Don't run down the road with the pressure water pump switch on.

Makes sense in retrospect and I won't moving forward, but can you give me a reason why? If it was running, where did it go? Curious minds want to know. :-)

OldCoot · 07-07-2013, 12:16 PM

Quote:

Originally Posted by _nelsonc

Makes sense in retrospect and I won't moving forward, but can you give me a reason why? If it was running, where did it go? Curious minds want to know. :-)

Leaking toilet and other faucets not completely closed?

**KyDan** · 07-07-2013, 12:59 PM

I lost half a tank on a rough road once.
Now if I am traveling with full tank of water I put a spring clamp on
the vent/over flow hose.
It's easily accessible inside my pass thru storage.
I also put a sticky note over the pump switch to REMOVE the vent clamp
B 4 turning on the pump.
Leave the vent clamped shut and you could collapse your tank!

Roll · 07-07-2013, 06:08 PM

Did you leave a low area drain open or the fresh water tank drain?

VinceU · 07-07-2013, 06:58 PM

Quote:

Originally Posted by _nelsonc

Recently spent 4 days dry camping in a local state park. Full fresh water tank lasted all four days. Filled up again and took off for Skyline Drive. By the time we got to the Lewis mountain Campground the tank was down to 1/3. The entire trip was spent on US50 and US33 so we are talking a roller coaster ride. Is it possible that the water sloshed out the overflow as I went up and down the 7-10% grades I was driving on?

I didn't notice the water was low till we stopped to take some pictures and I heard the water pump running when there wasn't anything on. There was a higher than expected amount of water in the rear black tank. But with the 66 gallon fresh tank and 45 gallon black tank, the 2/3 full black tank does not equal the 44 gallons missing out of the fresh tank.

This was on a 2013 Coachmen Mirada 35DL. Thoughts appreciated!

I think the pump running on occasion is insignificant. I believe like Kydan the loss was through the vent of the FW tank. By sloshing on a rough road, you can start a siphon effect and the rolls of water keep it going until the vacuum is broken at low level. Its been reported here a few times of folks losing water out the overflow. The vent should rise some distance above the tank but they don't, perfect scenario for a siphon effect.

garbonz · 07-07-2013, 07:05 PM

Quote:

Originally Posted by OldCoot

Leaking toilet and other faucets not completely closed?

X2. yer just lucky that nothing was closed and able to run over, and flood. I NEVER leave my water pump on when I am away from the camper. I ought to turn the camp site water off also, but I am to lazy. I should put a solenoid valve and switch in.

_nelsonc · 07-08-2013, 04:57 AM

Quote:

Originally Posted by VinceU

I think the pump running on occasion is insignificant. I believe like Kydan the loss was through the vent of the FW tank. By sloshing on a rough road, you can start a siphon effect and the rolls of water keep it going until the vacuum is broken at low level. Its been reported here a few times of folks losing water out the overflow. The vent should rise some distance above the tank but they don't, perfect scenario for a siphon effect.

I tend to agree. The drains were all closed, the sinks were all dry, and the toilets were not full of water. The wet bay was dry so the outside shower was not on. The only place this water could leave was through the vent. We drove half of Skyline Drive and quite a few mies on the Blue Ridge Parkway and there were several 7-10% grades along the way.

**Herk7769** · 07-08-2013, 06:33 AM

Quote:

Originally Posted by VinceU

I think the pump running on occasion is insignificant. I believe like Kydan the loss was through the vent of the FW tank. By sloshing on a rough road, you can start a siphon effect and the rolls of water keep it going until the vacuum is broken at low level. Its been reported here a few times of folks losing water out the overflow. The vent should rise some distance above the tank but they don't, perfect scenario for a siphon effect.

Agree; Once there is water in the vent hose, Venturi Effect will maintain the siphon until there is no way sloshing water can get to the vent line.

That will be "about" 1/2 tank. However, depending on how you park (levelness), 1/2 tank can leave the water level at the tank sensor too low to touch the 1/2 tank indicating sensor.

**KyDan** · 07-08-2013, 07:26 AM

I probably lost more like 1/3 tank as Lou's photo shows but we were
boondocking for 5 days and I was hoping to take at least a couple
brief navy showers! That 1/3 tank was sorely missed. Borrowed one
of those collapsible water jugs from a friendly neighbor and hauled
water on the 2 to last day. ( I own one now and after 3 years have
never used it.)
The spring clamp absolutely works. Last time I traveled with full tank,
I arrived at the CG with a FULL tank. Mine will fill in my driveway up
to the absolute top of the tank. There's barely an air bubble in there
when it's full.

As I mentioned- It's IMPERATIVE that you remove the clamp B 4 using
any water.

Happy Camping!

comfun1 · 07-08-2013, 08:08 AM

I can't say on your trailer but some new trailers have no vent tube, only a vent on the tank. If this is the case you can lose a lot of water from sloshing while driving. I have a 21rr and read about this on this forum. It was pretty simple and inexpensive to add a vent tube and prevent the water sloshing out.

_nelsonc · 07-08-2013, 03:32 PM

Quote:

Originally Posted by comfun1

I can't say on your trailer but some new trailers have no vent tube, only a vent on the tank. If this is the case you can lose a lot of water from sloshing while driving. I have a 21rr and read about this on this forum. It was pretty simple and inexpensive to add a vent tube and prevent the water sloshing out.

I have a 35 foot Class A motorhome. I am pretty sure I have an overflow as I fill the tank till the water comes out the overflow.

bend302 · 07-08-2013, 03:52 PM

I don't know much about Coachmen but my guess is that you watered the grass alongside the road.

On the Georgetown the problem is that the tank is very flat and shallow causing the water to slosh out.

The solution is a simple 1/2" valve from home depot Placed on the overflow pipe. There is a photo on here somewhere.

It works but you have to remember to open B4 use...

Bill

garbonz · 07-09-2013, 12:25 PM

So, not to hijack this thread, do you tow with the pressure water pump on?

_nelsonc · 07-09-2013, 03:01 PM

Quote:

Originally Posted by garbonz

So, not to hijack this thread, do you tow with the pressure water pump on?

I started the thread talking about a Class A motorhome and I was definitely driving with the pump on. Gonna skip that from now on based on feedback from the folks here.

garbonz · 07-09-2013, 04:40 PM

At least you are in the unit and can maybe see or hear if a pipe comes loose or whatever. I am concerned with my fiver springing a leak or a faucet vibrating open with all the bouncing and my fresh water tank empting on the floor. quack quack duck

Roll · 07-10-2013, 06:19 AM

I have, several times, traveled with a full fresh water tank. I'm no longer sure this is a good idea since pulling the additional weight affects gas mileage however I have never lost water doing this.

I know my overflow tube comes down off the top or near top of the fresh water tank and did terminate just over the drivers side rear leaf spring. I have since plumbed it to the side of the coach just ahead of the rear wheel on the drivers side. Did this so that I can more easily see it is full.

Anyway, I have never lost water and I am sure, since we use water on the road, that I have left the pump on. Neither the water nor the pump has ever been an issue for us.

Roll

cfsoistman · 07-10-2013, 06:27 AM

Same issue Georgetown owners have experienced. The vent is routed that as the water slooshes back and forth it syphons out the vent. Solution for my situation was to install a valve in the vent that I close as we travel and open when we arrive at campsite. Should we need water along the way I can always stop and open it, but you can flush the toilet a couple times without fear of collapsing the tank. If you look in the Georgetown area you'll find it to be a common issue.

_nelsonc · 07-12-2013, 04:20 PM

I have an update. I am dry camping this weekend. Now I have the water pump kicking on every 65-90 seconds for about a second to a second and a half. This was not happening before my last trip. I have looked for leaks everywhere, but can't find one. It sounds like there is a leak in the pump as I can hear water flowing back into the fresh water tank after the pump shuts down. I have an appointment with my dealer to have this looked at on July 27th.

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