Leak from top of black tank

There is a check valve in that connection. They are just under an inch long, and often people do not even recognize them. I might hazard a guess that someone did not blow that line out when winterizing, and there might be a tiny crack in the check valve that leaks down onto the black tank.

Take the screws off and the sealant, and pull out the water inlet screw-in connection, remove the check valve and replace it. They are cheap, less than $10.

One way of checking this is to disconnect from the water screw-in fitting, and try your pump. Leave the pressure on and see if the water leaks still.

It's worth just changing it.

I appreciate it. I’m in south Florida. No need for winterizing. Can you please be more specific on how to find that check valve. Sorry man I’m capable but a newbie

Likely where you connect the outside water hose there will be three screws holding down a round metal plate holding the hose connection. Take that off. The check valve is just inside there.

check valve

check valve for $10. WOW, mine cost $75. I took mine out and spliced in a solid piece and use a $3 check valve at the outer wall

awesomeman wrote:
Hi everyone. Having some minor issues with my Winnie 22m Minnie Winnie. It appears there is something leaking from the top of my black water tank. Here’s the thing.

It only leaks/seeps when I’m plugged into city water.

What do you guys think it can be? Trying to link a pic but it’s just water dripping down the side of the black water tank.

LOL. that just happened to me!
I thought it was the black tank also. I shut the water off and it stopped. So it's not your tank, it's a broken water line inside your coach.

Right above the black tank is where the small water lines run inside along the wall. You should have a raise along the wall inside where the nightstand/cabinets are next to the bed on both sides. That's where you will have to look to see which water line is leaking.

Ok. How does a check valve at fill in leak onto the top of the black tank on the other side of the rv. Not debating. Just have no clue. Lol. Thanks guys

awesomeman wrote:
Ok. How does a check valve at fill in leak onto the top of the black tank on the other side of the rv. Not debating. Just have no clue. Lol. Thanks guys

Water runs down the tubing from the water inlet, along whatever, and eventually drips down onto the black tank. Maybe it drips onto the black tank on the side nearest the inlet and flows across the tank.

It's also possible that something else is leaking and dripping onto the tank, though that seems a bit less likely since it doesn't happen when using the tank and on-board pump. Perhaps if the city water pressure is substantially higher than the pump water pressure it could be sufficient to make a loose fitting leak that otherwise stays dry.

DrewE wrote:

awesomeman wrote:
Ok. How does a check valve at fill in leak onto the top of the black tank on the other side of the rv. Not debating. Just have no clue. Lol. Thanks guys

Water runs down the tubing from the water inlet, along whatever, and eventually drips down onto the black tank. Maybe it drips onto the black tank on the side nearest the inlet and flows across the tank.

It's also possible that something else is leaking and dripping onto the tank, though that seems a bit less likely since it doesn't happen when using the tank and on-board pump.

Perhaps if the city water pressure is substantially higher than the pump water pressure it could be sufficient to make a loose fitting leak that otherwise stays dry.

Yup it can see post above.

I had a water line that runs above the tank break and when I connected to my city water it looked like a waterfall coming over the black tank. This will also happen using the water pump too.

First I thought it was tank also. I have high pressure water going to the inlet. Sadly I did 'not' have my water pressure regulator attached inline when I did it so it took the high power water pressure.

If you shut the city water off and the leak stops I.E. broken or leaking water line 'inside' the RV.

Where the floors meet the side of RV's is not air tight and water will fall thru this area to above the black tank and then drip down under the side.

If you want to confirm its a leak in the water line?

1. First if you shut the city water off and the leak stops.

2. Disconnect from city water and turn your water pump on. If it continues to run and does not shut off? It's a leak in a water line.

Good luck keep us posted on what you find. :C

Yes leak is only from city water plugged in. If I run off pump then no leak. I’m gonna r and r that pressure valve when I get home