Black tank valve issue

[LeBo]

I have to agree that the cause of hard opening and closing dump valve could be related to blade. I have a 2011 5th wheel 31RK that had a problem from day one. I took it apart and the seal had saw dust jammed in the groove where the blade goes. Works a lot better now.

[carl]

I put half cup olive oil with gallon of water in after last dump and when dumped a full tank today, it was amazing how easily it pulled! It sat maybe 2 hours with the gallon in it before we started using it again.

[avvidclif]

I had heard of olive oil and was going to suggest it, beat me to it.

Does Extra Virgin work any better????

Ducking and running.

[mark5w]

Last resort: Liquid-Plumr Urgent Clear. It is safe on all plumbing, Ingredients include sodium hypochlorite, sodium hydroxide, biodegradable surfactant, and sodium silicate (corrosion inhibitor). Contains no phosphorus.
Flows thru all the water to the tank valve. Wait 10 minutes and it should dissolve all the "stuff" around the valve.

[Ramn4ver]

Sawdust.... no way...lol...we been full timers for a year now. Still have sawdust in the heat duct after a year.
Thanks to everyone for their help.

Gary

[Dayle1]

I decided to try mineral oil to see if that helps, doing the grey valve 1st and then recycling it for the black valve. Will see if that helps before more drastic action. Also dropped the underbelly for a better inspection and didn't see a big issue with the cable routing, I could move it a few inches, then open and close the valve and it would still be in the same location, so problem may be the valve and not the cable.

There is just enough clearance above the existing valve location to mount a Drain Master electric valve. A vertical opening valve should suffer less buildup than the present horizontal valve. Just not sure I want to spend that much $$. So, I'm leaning towards replacing the cable valve with a manual valve. It would need a short extension and a hole thru the I-beam and would come out curb side and a few inches in front of the steps, so not too difficult to see or operate. I'm going to buy one to have available, then remove the cable valve and try fixing it, otherwise I'll stick the manual valve in.

[Russb]

I've had good results with TST Drain Valve Lube from CW.

[Ramn4ver]

We'll the mineral seems to be working. Only needed one hand to pull the black tank valve open today. Yee Haw...

[mark5w]

Glad your getting somewhere with your problem. That TST drain valve lube sounds like something we all should look into.

[Dayle1]

Originally Posted by Ramn4ver

We'll the mineral seems to be working. Only needed one hand to pull the black tank valve open today. Yee Haw...

Yeah, the mineral oil has improved my valves. Did the gray valve 1st, then the black. The black handle is still very difficult, but once it moves a little the effort drops to almost zero.

[Dayle1]

Originally Posted by Dayle1

Yeah, the mineral oil has improved my valves. Did the gray valve 1st, then the black. The black handle is still very difficult, but once it moves a little the effort drops to almost zero.

Well I'm now prepared if the mineral oil doesn't work over time, I will replace the black valve with a manual valve. Went to the local RV store and picked up a valve, then to Lowes for threaded rod and threaded coupler, total less than $25. Will carry this in the camper just in case.

[2slick]

The problem with our valve was apparently the long cable and it's routing. Pulled it out yesterday, and it works just fine. Replaced with an electric Valterra valve. Word of caution. The flange had to be trimmed for the Valterra brand valve. It is also difficult to get the valve in between the flanges. Love that easy to operate switch tho!

[moparguy62]

I have replaced many black water valves. The cable opperated ones are the worse and seem to pull hard. Two reasons, one is the valve the other is the cable, so between the two its double the resistance. Bleach is a issue for the valves DO NOT USE. I have found the gaskets look good but the new valves work great for a while. Grease isn't good for rubber products, the do make a valve lub that can be dumped in the black take. Hope this helps

[2slick]

Originally Posted by moparguy62

I have replaced many black water valves. The cable opperated ones are the worse and seem to pull hard. Two reasons, one is the valve the other is the cable, so between the two its double the resistance. Bleach is a issue for the valves DO NOT USE. I have found the gaskets look good but the new valves work great for a while. Grease isn't good for rubber products, the do make a valve lub that can be dumped in the black take. Hope this helps

I wish I would have straightened the cable out and tried with it still in place. It was very easy to operate once out of the flanges. Due to tank configuration, there is little room to spread the flanges. I would agree with not using the petroleum products due to the seals swelling. Funny thing....I just replaced the ball valve seal in our Thetford toilet.....RV parts store says lots of Vaseline on it. I use a tube of silicone lubricant. Seems it is made by SuperLube.

[r2millers]

We too have same black tank valve issue. Part of the problem, besides opening, is also closing the valve completely. Now I have to use a bucket under the dump opening when pulling off the cover due to a small black water valve leak.
I like the idea of Olive oil and will try that next.
Maybe the add on valve at cap next?

[moparguy62]

Originally Posted by r2millers

We too have same black tank valve issue. Part of the problem, besides opening, is also closing the valve completely. Now I have to use a bucket under the dump opening when pulling off the cover due to a small black water valve leak.
I like the idea of Olive oil and will try that next.
Maybe the add on valve at cap next?

Before add home remadies they sell a vale lube you dump into your tanks, made to help these valves. I also have found if there is not enough water used the toilet paper get caught in the valve. I use a bucket of water on top of the flush kit, it gives a greater rush of water when dumped into the toilet.

[bdwillie]

We had this problem with our 2012 cruiser too. Upon disassembly of the valve to change it, found flashing build up on both sides of the pipe that was crushed into the blade when the valve was assembled. Cut the excess flashing off the pipes and have been easy to operate since. A friend of mine has a 2011 slingshot, we just took his black water valve apart and same problem. Now his is effortless.

[2slick]

Originally Posted by bdwillie

We had this problem with our 2012 cruiser too. Upon disassembly of the valve to change it, found flashing build up on both sides of the pipe that was crushed into the blade when the valve was assembled. Cut the excess flashing off the pipes and have been easy to operate since. A friend of mine has a 2011 slingshot, we just took his black water valve apart and same problem. Now his is effortless.

I'm curious about the "flashing". The flanges actually have a raised area that pushes the seal against the valve blade. I think that is a design feature.

[bdwillie]

The flashing was what looked like a little thin extra bit on the exact bottom of both pipes on the flange that butts up to the seal. It was like excess glue from when the pipe was glued together, same color of the pipe. Quick swipe with a razor knife and it came right off both pipes. It looked as though these little protrusions were binding the seal/blade on both sides. unfortunately didn't think to take a picture. It was like an old model car kit, that had extra plastic that had to be trimmed off at the joints. Same thing. Hope I am describing this well!

Also my friends slingshot was exactly the same. swipe with razor knife and all is well

[2slick]

Originally Posted by bdwillie

The flashing was what looked like a little thin extra bit on the exact bottom of both pipes on the flange that butts up to the seal. It was like excess glue from when the pipe was glued together, same color of the pipe. Quick swipe with a razor knife and it came right off both pipes. It looked as though these little protrusions were binding the seal/blade on both sides. unfortunately didn't think to take a picture. It was like an old model car kit, that had extra plastic that had to be trimmed off at the joints. Same thing. Hope I am describing this well!

Also my friends slingshot was exactly the same. swipe with razor knife and all is well

I've got to open mine up again.....I'll have to look at that. I damaged one seal installing the new valve. Our black tank and galley tank drains directly oppose each other, so flange clearance to install valve was hard to obtain. I have a small drip on the valve.....not a good thing!