Black Water Tank Valve Leaking

Hello Everyone,

I'm a new member and this is my first post. I'm also relatively new to RVing, just over a year into a great lifestyle and my wife and I are enjoying ourselves. I've fixed a couple of problems already by myself, but need help with this one.

I've discovered the valve the is used to drain the black tank is leaking. Last time I drained all my tanks, there was very little liquid that came out when pulling/opening the black tank flush valve. I used the flushing system to clean the tank good, but now it's happened again. I know it is leaking by also, with the tank empty, adding a lot of water to the black tank through the toilet. I then went around the trailer and saw the water flowing in a little stream through the clear elbow I have connecting the outlet to my sewer hose.

I've downloaded the Heartland Owners Users Guide, Maintaining And Adjusting Cable Operated Tank Valves BH 3260EL, which seems good, but rather involved and complicated, especially since I would be on my back under the trailer and don't even know where the valve is with the bottom of the trailer all sealed up. I guess I better give it a shot before spending big bucks when calling an RV repair company. But if anyone has any experience dealing with this type of situation, fixing a leaking valve or replacing one, I would greatly appreciate any insight.

Thank you - Richard

Hi Teper,

If this is something relatively new, and it used to work correctly before, you may just have paper and waste jammed into the gate valve. The gate rides inside guides and if there's anything in the opening when you close the valve, it gets jammed in tightly. From that point on, the valve leaks a little.

If you're hooked up to the sewer and the black tank has a little leakage, the fluids in the tank drain out, leaving behind solids. That makes it harder to get the tank cleaned out, and more likely that you'll close the valve on more stuff that lays across the valve.

One thing to try is repeatedly filling the tank and draining. Use the time on your phone to make sure you don't overfill the tank, and never let yourself get distracted. If someone walks up and asks what you're doing, don't get into a conversation. The results can be very bad.

Another thing is to find a brush with stiff bristles and a long handle - like this one from Amazon. After repeatedly cleaning the tank, drain it and use the brush to try to clean the gate valve tracks. Then clean the tank some more.

If none of that works, you may have to take the valve apart. The difficulty can vary depending on model and floor plan. On many of the larger coaches with drop frames in front, you can take out the screws holding the coroplast in that corner to gain access to the valve. Use an impact wrench rather than a socket/ratchet. Much easier and less chance of shearing the head off the screw.

And if all else fails, you can pay to have it replaced. I'd think an experienced tech could do it in an hour - maybe a bit more. the valve assembly is inexpensive.

I think Dan has covered your options for fixing the problem pretty well. If you see water coming out with the valves closed you probably have paper jammed in the valve groove. I think that's what happens when people leave there black water tank valve open all the time while they are hooked up. For me the only time that valve is open is when I'm standing there dumping it.
Do you leave it open ?
My rig has a low spot in the line somewhere that holds some gray water in the line, then after I travel to my next destination and pull the cap off I'll get a cup or more of gray water behind the cap. I install a permanent gate valve before the cap. Some just run the spin on at the end of the line. Up to you. here's a link to my Project LM 365 thread.
https://heartlandowners.org/showthread.php/54076-Project-LM-365?p=450833&viewfull=1#post450833

Or get one of these at Camping World ($25):

Thanks for the idea Thornton. I may try that out if I can't get the dedicated valve fixed.