31SL black water tank removal

[max3140]

Anyone had the pleasure of removing the black water tank out of a 2013 31 SL? Water leaking from a grey water tank (I think) above it Thank you

[mhs4771]

Tanks are generally side by side, don't know of any one on top of another.
I know my black and gray (bathroom/shower/washer) are in the drop frame section side by side, while my galley and half bath (if we didn't have the Butler's Pantry) are in the belly just in front of the axles side by side while our fresh water tank is just behind the axles.

[max3140]

Originally Posted by mhs4771

Tanks are generally side by side, don't know of any one on top of another.
I know my black and gray (bathroom/shower/washer) are in the drop frame section side by side, while my galley and half bath (if we didn't have the Butler's Pantry) are in the belly just in front of the axles side by side while our fresh water tank is just behind the axles.

Unfortunately on the 31sl the 2 grey's are mounted above the black ahead of the axle
Thank you Michelle & Ann for responding

[mhs4771]

Must be with the shorter length of the 31SL they didn't have the room for the typical side by side configuration.

[NW Snowbirds]

We have a 2012 31SL and the gray tanks are stacked as you described. Are you sure that there is a leak in the gray tank or could it possibly be in the vent line from one of the tanks. I thought we had a leak when the shower overflowed and water poured out from the black Coroplast. It turned out that the factory forgot to glue a vent line coupling just above the top tank. When the overflow ran up into the vent line it leaked out of the loose piping union. Fortunately I was able to get at it behind the basement wall.

[max3140]

I can see with a bore scope the water leaking from the termination valve area shortly after the tank starts to fill with water
Appreciate your response
Gary

[Terry S]

Don't envy you this job! I also have a 2014 31sl. If you don't mind please keep us posted on how you tackle the job. I'd also love to see a few pictures of the belly with the complast removed. Would love to know where and how they secured things and if there are other preventative maintenance issues that should be prepared for if one ever has to remove the complast.

[NW Snowbirds]

Originally Posted by max3140

I can see with a bore scope the water leaking from the termination valve area shortly after the tank starts to fill with water
Appreciate your response
Gary

You could have something stuck in the valve. Maybe try shoving a hose up the drain pipe and flushing vigorously from outside.

[max3140]

Will do. I removed the washer dryer prep some years ago from the front closet to allow the left closet door to open fully so now all that goes into the passenger side grey tank is the bathroom and kitchen sink. BTW Termination valves were labelled incorrectly so grey handle was actually galley tank

[woodman1]

We have a 2017 36RL and the grey and black tanks are stacked, not side by side. Once you open the belly of your unit, you can have someone try to operate the gate valves from the control center while you watch from below to determine which is which. I'm thinking of changing out the gate valve to the black tank because it's so hard to open and close. The larger of the gate valves, usually 3 inch, goes to the black tank and the smaller gate valve to the grey. In our case the black tank is situated above the grey tank, which means it will be much more difficult to access from below. There's plywood above, which makes that access impossible. If you think about the length of the cable running to the gate valves, you can see why it's so difficult to operate. Too much slack in the line.

[Terry S]

Just a thought for discussion: If you don't need to remove the tank and know the exact location of the valve. Might it be possible to access the valve from above by pulling up the living room carpet and then cutting an access hole in the living room floor with a plunge cut? I'm figuring the removed floor piece would be spliced back in using techniques that we use on normal floors or walls and then recovered with the rug or linoleum Even if the valve is under the linoleum I'm thinking that might be easier than pulling the complast and bottom tank just to get a valve?

[woodman1]

Our tanks are below the furnace and water heater making it impossible to access from there. Most tanks are low and within the frame.

[max3140]

Originally Posted by Terry S

Just a thought for discussion: If you don't need to remove the tank and know the exact location of the valve. Might it be possible to access the valve from above by pulling up the living room carpet and then cutting an access hole in the living room floor with a plunge cut? I'm figuring the removed floor piece would be spliced back in using techniques that we use on normal floors or walls and then recovered with the rug or linoleum Even if the valve is under the linoleum I'm thinking that might be easier than pulling the complast and bottom tank just to get a valve?

The valve is approx below the fuse panel wall and I hesitate cutting a hole in the floor as I only suspect the valve but it may be a cracked tank. I have it partially disassembled now so will pull tank to be sure I can address. Will report back when job complete
Thank you

[max3140]

Update
Problem was a cracked 1.5 inch ABS union on the outlet of the gray water (galley and bathroom sink) tank. Removed front belly pan, then cut 3 inch ABS pipe from toilet about 3 inches above entry to tank, then disassembled gate valve so outlet could remain and disconnected the vent pipe connected up on shelf behind central vac followed by removal of the rear bracket that holds black tank in (screws holding bracket go from inside through frame)- not easy to access. Dropped tank to find broken union. Reconnected 3 inch ABS at tank with rubber flexible coupling. Problem solved. Very difficult to get good pics in the limited space and not sure how to include ones I took….Thanks for all the input

[shrode]

Originally Posted by max3140

Update
Problem was a cracked 1.5 inch ABS union on the outlet of the gray water (galley and bathroom sink) tank. Removed front belly pan, then cut 3 inch ABS pipe from toilet about 3 inches above entry to tank, then disassembled gate valve so outlet could remain and disconnected the vent pipe connected up on shelf behind central vac followed by removal of the rear bracket that holds black tank in (screws holding bracket go from inside through frame)- not easy to access. Dropped tank to find broken union. Reconnected 3 inch ABS at tank with rubber flexible coupling. Problem solved. Very difficult to get good pics in the limited space and not sure how to include ones I took….Thanks for all the input

Was there not a way to disconnect the toilet from the back tank without cutting the pipe?

Also I'm curious how your gray tanks are plumbed. On my 2017 31SL, the shower, kitchen sink, and washer are all plumbed to the Galley tank. The only connection to the Gray tank is the bath sink! We don't have a washer so it's not a problem, but I can't believe they plumbed it this way. I installed a gate valve in the 3" drain line so I can equalize the two tanks to get the full capacity when we don't have sewer hookups.

[Terry S]

Thanks for following up. Good to hear you didn't have to drop the tank(s). Wonder what stressed that union to where it failed?

[max3140]

The 3 inch pipe was in its happy place so rather than chance breaking it removing, it was easier to cut the pipe. My bathroom sink and kitchen sink appear to drain into galley tank while the shower and washer prep drain into gray