The Galley Tank Dilemma - 2006 3670RL

[EllsworthToohey]

Here is my latest maddening event. I have a slow drip leak from the Galley tank below the Kitchen Sink. Its not a major leak but I do not want water pooling up in the plastic under belly panels, so I decided to drop the tank for easier inspection and repair.

1st thing I did after watching several videos on tank removals, was to cut the straight down pipe into the tank above the floor to pull out to free the tank. I expected the pipe to be removable but it will not budge! This now gets critical, because:

The galley tank is held in place by frame cross members supporting it by the flange around the top. To remove the tank the rear cross member can be removed with 2 bolts at each end. Separate the exit plumbing at the gate valve. Disconnect the sensor wires and it will slide toward the rear of the trailer and then drop out after an inch or two move. Ooops! It cannot move because the drain pipe is glued into the top inlet!!!

The forward cross member is WELDED in place! Only the rear Xmember is removable. This is a monster dilemma. I cannot remove the tank because the drain pipe prevents sideways movement and the welded xmember prevents dropping vertically!!!

Has anyone ever run into this situation? Any recommendations short of just destroying the tank to get it out?

Tank has obviously been removed at some point in its life because there were a complete set of new sensors installed right next to the original ones. So this sounds like whomever reinstalled it, did not think about what they were doing when gluing the down pipe into the tank thru the kitchen floor.

Grrrrr. Help!

[Carl n Susan]

To be honest, I haven't watched the removal process that closely to remember how they extracted the tank. It seems to me, there are two options.

1. Cut the down line below the floor level to allow it to slide the few inches it needs. The new tank, if this is what you are planning, comes without the hole for the down pipe. You will get to drill the hole and attach the new pipe. No-hub fittings are your friend to reconnect the cut plumbing lines.

2. Elongate the hole in the floor to allow the down pipe to move the needed inches. There usually is a white plastic collar around that down pipe to cover the gap. I would think the hole underneath it is adequate to allow movement. If it isn't, make it bigger.

[EllsworthToohey]

Hi Carl, I was thinking about that as one of the only viable options. Its just a very awkward location to get any kind of saw in there under the sink, and the danger of cutting thru the floor and into the tank. I have one other possibility. Today i made a measurement of the pipe center from the front and side walls under the sink and indexed it to the window above the sink. I can see the window from outside, to establish where the pipe is from the edge of window. This revealed that the drain pipe is very close to the edge of the tank. I might be able to get a super thin blade like a hack saw blade between the floor and the top of the welded cross member. This would allow sawing the drain pipe flush with the bottom of the floor. This would make it all but impossible to reuse the tank though, unless I do creative plumbing into the now reduced diameter of the inlet. I will give the floor notching more thought. It would let me reuse the tank with the existing cut pipe stub.

[Carl n Susan]

Poke a tape measure down the hole in the floor to see what the clearance to the tank is. I suspect there is at least 2". I would use a Dremel with one of its rotating saw blades to extend the hole an inch in the direction needed for removal. The blades cuts with the side of the tool, but the bottom won't drill into something below.

[EllsworthToohey]

Hello again Montana members. When last we met, the issue was fully cemented drain pipe into Galley Tank beneath Kitchen sink. I did manage to cut a square extension of the drain pipe hole to allow the tank to slide sideways with the pipe sticking up thru the floor. Success! rite? Not so fast Mr Newbie, you neglected to notice your next obstacle - the welded steel flat that runs right across the middle of the Galley tank! Yikes! This means that the tank must slide at least a foot to clear this weldment, and that is impossible!

What to do what to do? Well face the reality Newbie.... Yer gonna have to CUT OUT this offending steel flat bar!!! The only function this bar serves is to provide screw attach points for closing up the belly panels, so next step is to measure how long this bar is and find a suitable length of flat steel bar or aluminum sq. tube to bolt into the steel RV frame, so next time access can be had with a wrench instead of a saw.

Do these folks ever grasp the fact that the stuff they build breaks down a LOT and requires access to the broken parts?!?!?! Almost seems as if they don't!

Anywho.. that is why forums like this are so valuable! I appreciate all the advice.

[EllsworthToohey]

Crawling under to measure the length of this welded bar proved it to be an L angle steel not flat, but the length is 68" which is excellent because Lowes has such pieces in 6ft lengths. But latest thinking is to use a dremel with a cutting disc to grind away the welds and knock the full length steel member out and reuse it. This time though instead of welding I will try drilling and using more 3/8" self tapping screws to put it back. This will permit much easier servicing in the future.

Who wants to join me in starting an RV company that makes a quality trailer that is designed for servicing? Easy access to all serviceable items... Manuals that completely inform the owner.. Carefully routed wiring and water lines that do not resemble a bowl of spaghetti. Imagine the legends we'd become!!!

Well that dream is for tomorrow. Today is grinding day. Winter is coming.

[EagleRunner]

I would suggest that before going to the difficult task of removing and replacing a waste tank you take the time to locate the leak. Most leaks are caused from stress which causes stress cracks. If you can locate the leak and can get access to it you can fix it using a product called Plasti-Mend. This product came about from an RV Tech whose job was to replace these tanks and found doing so was costly and more often unnecessary when a patch solution would resolve the problem. This product, when applied properly, makes the patch area stronger than the original tank. But the crack and adjacent area must be throughly prepped before attempting repair.

Do a search for Plasti-Mend for product details and use.

I have patched two of my waste tanks and have not had another leak since and it’s going on six years.

Good luck in your tank repair!