Fresh Water Tank

[HDRider]

Or, the mystery of the leaking weep holes.

 

I hope someone here can help me understand what is going with the leaks from the weep holes.  I will state what I know as fact.  Some of what I say will be conclusions I have come to based on evidence and experimentation.

 

We took off June 1st.  I noticed the weep holes leaking the morning of our first overnight stay.  It was leaking pretty good from the weep holes in front of the steps.  It is not a stream.  It is a drip, drip, drip kind of thing.  I have looked everywhere except under the bathroom sink.  No water anywhere.

 

Clue #1.  It only leaks when the fresh water tank has water in it.  Fact

Clue #2.  The water pump kicks on about every 30 to 40 minutes when the fresh water tank has water in it.  

Clue #3.  I am pretty sure the leak stops if I turn the pump off.  I have done this a couple of times, and I am pretty sure this is true.  There are no leaks around the pump.  I have checked multiple times.

I have been working with Oliver.  We think a fitting has come loose.

 

But,

Mike asked me if we filled the fresh water tank until it overflowed.  We do.

So,

Yesterday I filled it to 80%.

No leak this morning and the pump did not kick on while there was no water use.

[HDRider]

Also,

The leak is not isolated to any one set of weep holes.

 

It always leaked out of what was the lowest corner at the time.

[routlaw]

I will take a stab at this. By filling the fresh water tank until it overflows via the weep holes you now have a tank that is so full the water will tend to flow out of the lowest point. Understand too the bubble level at the front is NOT a perfect indication of true level until its calibrated to a known source. What I am getting at is unless you know there is water leaking between the hulls I wouldn't worry about it too much so long as it's coming out of the weep holes. 

However one way to check this is take your kitchen drawers completely out of the cabinets and with light in hand peer over to the outside of the trailer, backside of the cabinets at the floor area to make sure nothing is leaking into this area caused by a bad fitting. You could also prevent this by shutting of your water supply during fill up when tank indicator states 100%. On my Ollie even after 100% indication the water will keep filling for another few gallons until it overflows via the weep holes

Hope this helps

Rob

[Mike and Carol]

Rob, are you talking about the fresh water overflow port or the weep holes?  When I overfill the fresh tank the excess water comes out of the overflow port behind the steps, never out of any weep holes.

I don’t have any thoughts on why it doesn’t leek at only 80% full, but leaking only when pressurized usually indicates a leak somewhere.  I had a plastic pex T-joint that came out of the hot water tank which had a small crack.  It was fine until pressurized, then it was a steady drip.  It took some time (and some blue paper towels) to find.  Mike

[HDRider]

39 minutes ago, routlaw said:

I will take a stab at this. By filling the fresh water tank until it overflows via the weep holes you now have a tank that is so full the water will tend to flow out of the lowest point. Understand too the bubble level at the front is NOT a perfect indication of true level until its calibrated to a known source. What I am getting at is unless you know there is water leaking between the hulls I wouldn't worry about it too much so long as it's coming out of the weep holes. 

However one way to check this is take your kitchen drawers completely out of the cabinets and with light in hand peer over to the outside of the trailer, backside of the cabinets at the floor area to make sure nothing is leaking into this area caused by a bad fitting. You could also prevent this by shutting of your water supply during fill up when tank indicator states 100%. On my Ollie even after 100% indication the water will keep filling for another few gallons until it overflows via the weep holes

Hope this helps

Rob

There is an overflow as described in the Owners Manual.

TO FILL THE FRESHWATER TANK FROM PRESSURIZED WATER: 1. Remove the cap from the freshwater inlet. 2. Attach a freshwater hose to an outside water source. 3. Attach the other end to the Oliver freshwater inlet. 4. Turn on the water source; fill until water starts to run from the freshwater overflow, which is located on the opposite side, between the aluminum steps and the refrigerator vent. 5. When the tank is filled, turn off and disconnect the outside water hose and re-install the water cap.

 

The weep hole leak comes later.

 

You have confused the weep holes and the freshwater overflow. 

[HDRider]

20 minutes ago, Mike and Carol said:

I don’t have any thoughts on why it doesn’t leek at only 80% full, but leaking only when pressurized usually indicates a leak somewhere.

The 80% thing has me scratching my head.  Thought - Is it possible for the freshwater overflow to spill water in the hull?  Then it would leak out.  Saying that - Why would the leak continue on for so long and so steady?  More head scratching....

 

When you say "only when pressurized", what does that mean?

[HDRider]

Question - If the freshwater tank is full to the top how does air come in as water is pumped out?  Put another way - How does a vacuum not form in the freshwater tank?

[Mike and Carol]

27 minutes ago, HDRider said:

When you say "only when pressurized", what does that mean?

By “pressurized” I mean either water pump on or connected to city water.  While there can be residual pressure even when the pump is off and there is no connection to city water, if there is a leak in the system, that pressure will steadily lower through the leak to the point where there is no pressure in the system.

[Mike and Carol]

30 minutes ago, HDRider said:

Question - If the freshwater tank is full to the top how does air come in as water is pumped out?  Put another way - How does a vacuum not form in the freshwater tank?

I think the freshwater overflow must allow air in .

[HDRider]

@Mike and Carol

 

Thanks

 

What you are saying is helping!

 

I am really thinking there is a leak at a fitting.

 

The big fat open question now is: Why is it not leaking now when I did not fill to overflowing?

[Snackchaser]

I'm not exactly clear on what is meant by the weep hole, but I can share what I have experienced:

1. The freshwater tank overflow also acts like a vent to prevent a vacuum as the tank is drained.  
2. I have noticed that when the tank is full, the overflow may start dripping again later due to thermo expansion or a change in the trailer level.  
3. A failing pump can cycle as if there is a slow leak because it's internally leaking from the low pressure intake side to the high pressure output side, even though there is no visible leak to the outside of the pump.  A leaking pump internal check valve can also cause water to leak back into the tank, and potentially overfill again.  If you think about it, all the water on the pressurized side, including the water heater and accumulator, can flow backwards through the faulty pump check valve and into the tank and you would only notice it if the tank was full and overflowing again.

Hope that helps!  Geoff

Edited Friday at 04:29 PM by Snackchaser
added detail

[Mike and Carol]

33 minutes ago, Snackchaser said:

A failing pump can cycle as if there is a slow leak because it's internally leaking from the low pressure intake side to the high pressure output side, even though there is no visible leak to the outside of the pump.  A leaking pump internal check valve can also cause water to leak back into the tank, and potentially overfill again.  If you think about it, all the water on the pressurized side, including the water heater and accumulator, can flow backwards through the faulty pump check valve and into the tank and you would only notice it if the tank was full and overflowing again.

I’ve been experiencing this for the last couple of years.  About every 3rd camping trip, while connected to city water, I get and fast drip from the overflow.  I go inside, check that the fresh tank is at 100%, turn on the water pump and turn on a faucet for a couple of seconds and the problem is solved.  I bought a new water pump when this started, but I just haven’t gotten around to replacing the old pump since is doesn’t happen very often and when it does it’s a quick fix.  I keep the water pump in the trailer hoping that it will threaten the old pump to behave, but it’s not working.  Mike

[HDRider]

1 hour ago, Snackchaser said:

I'm not exactly clear on what is meant by the weep hole, but I can share what I have experienced:

1. The freshwater tank overflow also acts like a vent to prevent a vacuum as the tank is drained.  
2. I have noticed that when the tank is full, the overflow may start dripping again later due to thermo expansion or a change in the trailer level.  
3. A failing pump can cycle as if there is a slow leak because it's internally leaking from the low pressure intake side to the high pressure output side, even though there is no visible leak to the outside of the pump.  A leaking pump internal check valve can also cause water to leak back into the tank, and potentially overfill again.  If you think about it, all the water on the pressurized side, including the water heater and accumulator, can flow backwards through the faulty pump check valve and into the tank and you would only notice it if the tank was full and overflowing again.

Hope that helps!  Geoff

There are 8 weep holes, two at each corner of the trailer.  They have a little stainless steel covers over them.

 

The weep holes are separate and apart from the freshwater over flow.

 

The pump cycling only happens in conjunction with the weep hole leak.  

[topgun2]

1 hour ago, Mike and Carol said:

I think the freshwater overflow must allow air in .

yes

1 hour ago, Snackchaser said:

The freshwater tank overflow also acts like a vent to prevent a vacuum as the tank is drained.  

yes

The 80% fresh water tank being full and no leak while the fresh water tank at 100% full has a leak indicates to me that your leak is probably happening at or near where the overflow tube is "attached" to the fresh water tank.  

Bill

[Snackchaser]

12 minutes ago, HDRider said:

There are 8 weep holes, two at each corner of the trailer.  They have a little stainless steel covers over them.

 

The weep holes are separate and apart from the freshwater over flow.

 

The pump cycling only happens in conjunction with the weep hole leak.  

Oh, okay.  In that case, @topgun2 had a good notion that it's leaking where the vent line connects to the top of the freshwater tank,   However, that doesn't explain why the pump is cycling . . . unless the pump check valve is leaking by; back-filling the tank from the pressurized side, and then leaking where the tank vent is connected to the top of the tank. . . and it would only be noticeable when the tank is full!

Are we getting closer?  Geoff

[topgun2]

2 minutes ago, Snackchaser said:

Are we getting closer?

I hope so!😁

[STEVEnBETTY]

I can’t explain why the pump comes on every 30 minutes or so, but in the first year of ownership,my fresh water tank overflow leaked internally at that fitting. The fix Oliver came up with was to drill a hole in the bottom of the kitchen cabinet under the sink and tighten the hose clamp on that fitting. It only leaked when the tank was overflowing.

[HDRider]

20 hours ago, topgun2 said:

The 80% fresh water tank being full and no leak while the fresh water tank at 100% full has a leak indicates to me that your leak is probably happening at or near where the overflow tube is "attached" to the fresh water tank.  

Bill

That makes sense.

[HDRider]

We have been on the fresh water tank all day yesterday and all night.  It is 7 AM local time Saturday.

 

I filled the tank to 90% and hit the road yesterday morning.  We were on FW tank all day Thursday and Friday.

 

We have been on the FW tank now for 3 days.  Pump is normal.  No leak.

 

 

[HDRider]

18 hours ago, STEVEnBETTY said:

The fix Oliver came up with was to drill a hole in the bottom of the kitchen cabinet under the sink and tighten the hose clamp on that fitting. It only leaked when the tank was overflowing.

That must be a standard now.  Oliver had me take the wood cover off under the kitchen sink.  I checked and it was not wet.

[HDRider]

I will fill to overflow and see if any new clues show themselves.

 

I guess I'll be taking the trailer to Hohenwald when we get home.

Edited Saturday at 02:22 PM by HDRider

[bugeyedriver]

Several years ago, The Wonder Egg had the similar symptoms.  Ultimately, my local RV mechanic diagnosed a leak at the point the water leaves the fresh water tank and starts its journey up over the arch of the hose to the overflow exit point.  Water was escaping and finding its way down into the lower section of the basement and out through the closest weep hole underneath the trailer.   It was a head scratcher for a bit, but after stemming the leaky hose/tank joint all was well with the world.

[HDRider]

I have come to the conclusion it leaks when the pump runs.  Not sure where.  I have looked everywhere but under bathroom sink.

 

Not sure why the pump cycled like it did.  It has not recycled since I only filled to about 90%.  Now it only runs when we use water.  Maybe it went into some kind of vacuum spasm when I use the overflow outlet..