Dump Valves

I had an impossible fit to remove and replace either valve. The piping was, obviously completed and the trailer built around it. As several have suggested, the best solution is, or was for me, to hacksaw both, the black water and gray water lines, removed the valve assemblies and reinstalled them with rubber couplers after replacing a bad blackwater valve.

Found that the manufacturer had allowed glue to leak into the valve, preventing complete closure.

jparker66 wrote:
Part are not that expensive and since most local places charge $110 an hour, I am better off doing this simple job.

I've been RVing for 25+ years, 2 different MHs, and never replaced a valve. If you've replaced yours 3 times, something's wrong. Once, OK. 3 times = installation failure. Maybe you're "not" better off doing this simple job; maybe it's time to spend the money to have an RV service place do it this time?

I would leave the twist on on just for ease of mind.Knowing I'm not going to get stinky water up my shirt sleeve,means a lot to me.My black dump cable broke and didn;t shut.When I went to dump,WHAT A NASTY SUPRISE..Twist on keeps that from ever happening again.

CT,
Great idea! The trouble I had when I last installed both valves was the "binding" as I lifted the entire assemble up and back in place. The is another very bad design by the RV industry. Look at my pic-- they place a piece of black round pipe as a spacer and then put the Stainless Steel Plumber's Tape / Strapping to hold the entire pipe assembly. As you can see they did further rigging by using a screw on the side of the spacer--which has come out. This is the main purpose of my initial post. Has anyone created a modification that is better? More professional?
Thanks CT,
James

For some reason the black tank valve is always harder to pull than the grey tank valve, and needs to be replaced more often. As you have already guessed your seals are probably binding. What I did when I replaced my BT valve is to put grease fitting on the top of the both valves to lubricate the blade seal. I did this about 7 years ago and pump some grease in when it becomes hard to pull. The grey water valve is 20 years old and still has never leaked. The BT valve needs some grease about every other year to remain easy to pull and leak free.

I think that during travel you are moving some of the residuals out of the tank as was previously mentioned. This might actually be a good thing since that seems to be the only way it will come out. So why not roll with it and just put a valve at the exit so you can control the event, When you get home, put a 5 gal under there and open the new valve and know that you are cleaner then before.

Have you seen this video? It opened my eyes to what really goes on "in there"

Dumping comparison

Researched and here is my picture. I really looks easier than I thought to put two separate drain valves, but I prefer not to go that route.

Thank everyone for your comments.
Additional comments: To clarify my first post--when I replaced both valves, it is extremely tight. I can get one on, but when I start on the second one I have to push the entire T up in place. This is when I feel I am damaging the gasket. I have a flush system that came with the camper. I connect a hose to an outlet on the camper, turn the water on, open the black water valve and it works like a washing machine. So, the black tank gets emptied. I go home and the next time I go camping and hook up the sewer hose, some stinky brown water comes out. I feel sure it is the black water tank and not the grey water tank. Same thing happened last weekend. I went camping, really flushed it out till clear water was seen and went home. Today, I went to the barn to check it out. A small amount had leaked past the valve.

I have a picture, but have not figured out how to post it.
Thanks again,
JP

The twist on is your best bet. Didn't realize the black valve was leaking slowly draining out the liquid leaving the solid. Wouldn't dump, a lot of work with a drain auger and it loosened up and drained. Added the twist on and problem solved. Ron

The service manager I talked to said that some water is left in the pipes after dumping. That not all of the sewage drains from the pipes, especially if you dumped at an angle. and then with the motion of the trailer on the trip home and to the next campsite the water accumulates at the drain cover.