Gray water tank

[Mike117]

Out camping and using the shower with the drain system closed to discharge. No problems. Leaving camp ground and was draining gray water from shower and sink. Wife was taking a shower at the same time. Water began to fill up in the underbelly and began leaking out. Not sure why this would happen. At another location now discharge handles in and using shower no problem. Any ideas on what happened? Will take it in and have it checked out when I get back. Seems strange to me, why if the system is open and shower running while draining it would leak. Don't think it is the tank. My guess leak at the plumbing of the discharge handle. Not sure using correct terminology but it is slipping my mind.

[Carl n Susan]

I have a friend who had the same symptoms on his SOB. It turns out the downstream side of the gate valve was leaking. It was fine as long as the valve was closed, but once it opened, it would leak.

You don't say what model and year Montana you have but those with the dropped frame make it easy to access the shower tank valve. There were several postings on this subject in the last few weeks. They related to the black tank but the shower tank is next to it and the same principals apply.

[Mike117]

Sorry 2014 High Country 343rl. Frustrating but not the end of the world. 4th time out and no issues but thought it was strange and I am anal about having everything work and maintenance. I knew someone would know with all the knowledge. Much appreciated.

[Art-n-Marge]

Common problem is that as the tank fills, and gets too full, a leak may occur where the plumbing enters the neck of the tank. I try not to let my tanks get too full to avoid this problem. Not sure if you are describing the same problem, since it appears to leak when the valve is open.

My rig has been doing great for the first nine years of ownership, but finally during the past year, I have noticed this occurrence if I do not stay on schedule for dumping my 2 gray tanks.

Every couple of days, both galley and gray (shower/lavatory), get dumped because I try and fill them up before dumping, since I think this keeps the tanks cleaner. On the sixth day of this cyle, I dump the black first, then follow it with dumping the two gray tanks to clean any black stuff from the drain plumbing. Following this schedule helps me avoid the leakage at the top of the tank.

One of these years I'll have it looked at, but since it's a lot of labor cost, I'm trying to avoid it for as long as possible.

Anyway, the point being it's one thing to look for (a leak at the neck of the tank.

[Mike117]

Thanks Art for the info. I dump like you do every couple days. So in this case I know the tank was not full. I will look at it when I get home. At least I am glad the tank is not leaking. Must be an issue when valve is open and dumping and running the shower. Just hate when things don't work correctly.

[rohrmann]

The problem is probably in the 3 inch waste line from the tank, after the valve. The way these are put together, there is no ability for the system to flex, as the black and grey tanks are plumbed to a common wye fitting, and then out to the discharge line. We had the black tank valve and both flange fittings on either side of the valve break several years ago, probably from not being able to flex. CW in Idaho made repairs, and when putting it back together, they put a 3 inch rubber coupling between the elbow at the valve and the wye fitting. Haven't had any problem since.

[mboys]

I'm having a problem with grey water tank leaking after about 2-4 showers, not enough water to fill the tank. It starts leaking through the underbelly. Not able to see what or where it's leaking from the tank until I (or CW) exposes the tank. Anyone have an Idea of how much it cost to replace a grey water tank if this is required??

[Mike117]

I don't know but good luck. Not sure why these tanks would leak.