Leak, or what?

[MEIGSX2]

Where is the water coming from? 2019 Freedom Express 246RKS. Recently removed stabilizers to detail them (nasty looking and some rust) I was very surprised to see rust along the perimeter of the frame where underbelly attaches. Heavy rust in some places. Had to use my air de-scaler to remove.
To keep it brief. The porous edge of underbelly (like a yard sign) was weeping water. A 1/4" hole in the center of a sag in the underbelly, in the front, let out about a gallon of water. Removed underbelly and found more rust where underbelly was attached and could not be seen. There was evidence that water had pooled in the forward section of the underbelly. (rust rings). The most forward holding tank is grey water. The hose clamp where the plumbing pipe attached to the tank was rusty (the screw portion, not the band) )(haven't replaced yet). So It appeared to be the source of the leak. Filled the gray tank 2/3 and no leak! Three days and not a drop. Now I've filled the black tank and still no leak! Attached city water to trailer, no leaks. Turned on and off, one by one, all water faucets. Observed and no leaks. (btw. I park my TT on the side of my house where i have a 30amp connection and a sewer cleanout. fyi) I'm letting it sit and keeping a eye out for water. Somehow water got in my underbelly. And it's been there for some time (off and on??) due to the amount of rust i saw. And it's only on the frame forward of the axles. Tried to get Coachmen (Forest River) to send me a plumbing diagram. That was a joke. Sorry this was so lengthy. But has anyone with this, or a similar rig experienced this issue? Thank you! John

[TitanMike]

Have you ever traveled down the road in the rain?

I've had the belly cover down on my TT for some upgrades and the first time I got a lot of water from the edges of the coroplast. Also some small puddles had formed on the top side that also left some dried mud where the water had evaporated.

I know I had no water leaks in my plumbing system as I rarely use city water (hard core boondocker here) and the water pump is off whenever I'm not using water.

I put some aluminum HVAC tape around all the edges of the belly cover to seal it off from road spray and the next time I lowered the belly cover the only water on top of it was in the vicinity of the two air vent louvers.

That said it's possible that water can find it's way onto the cover if tank filling allows water to leak from vent or overflow.

If you want to check system for water leaks consider installing a Tee at the city water connection with a valve and pressure gauge. Pressurize the system with city water, turn off valve, and observe pressure gauge. If it holds steady with no water entering from city source, no leaks. Compressed air can be used too but pressure loss using water will show up quicker as there is very little air in the system to bleed down before gauge drops.

[MEIGSX2]

Thanx T/Mike. I started trying to figure out this problem about 2 weeks ago. TT had been parked in our side yard since mid July after getting back from Moss Park in Orlando (great county park btw). So it's extremely puzzling why water was in there. You'd think it would have evaporated by now. And now almost 2 days have gone by with grey and black tanks @ 2/3's and no sign of a leak. The only thing I haven't done yet is walk the roof. Since we live in East central Florida we get, and have been getting, lots of rain. Water does travel far distances at times so maybe I'll find my issue on the roof somewhere.
I am going to follow your advice on the hvac aluminum tape for sure.
Thanx! John