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Topic: Black tank mystery (Read 1879 times) previous topic - next topic

Re: Black tank mystery

Reply #40 –
I have just installed two new valves and I will incorporate this technique when its time for lubrication.  Thanks TM.

jk

Re: Black tank mystery

Reply #41 –
Be sure to verify that the lube you use is compatible with the blade seals.  I am not saying that there is a problem, but, for example if you use a petroleum-based lube on rubber, it will help short-term, but swell the seals.

If someone KNOWS what material the seals are made of, we can post that so everyone will know.

Re: Black tank mystery

Reply #42 –
Sears.com

Re: Black tank mystery

Reply #46 –
I can't remember where I heard, saw, or read it now but someone drilled the blade housing and installed a zerk fitting in it. I thought that was an interesting idea, but I don't know of any grease I would want to use there that goes in a grease gun. I think drilling a hole and spraying some pure non drying silicon is what I will do. I was able to spray the third valve and the gray valve by just disconnecting the hose because it is a straight shot through the opening. It is quite effective, and can easily be renewed if it gets sticky again. But the black tank valve is around the corner and farther back, so the method in this video should work. Fortunately, my utility bay set up makes it very easy to access the valve assemblies.
Don
Quote from: Travelin' Man –
Not to hijack the thread but I like this approach to lubing the valve blade;

https://m.youtube.com/watch?v=TGv9THpOdmw

Re: Black tank mystery

Reply #47 –
I think it was Carol & Jeff who I purchased the coach from who told me this tip.  Put some vegetable oil down the sink and toilet and operate the valves.  Lubes them for a while.  Works for me.

Keith

Re: Black tank mystery

Reply #48 –
I to have made that modification and have been useing white lithium grease. Don't forget to put the sheet metal screw back in after you lube! Got distracted and missed the one on the black tank. Simply amazing how much stuff can come out of such a tiny hole. Felt like the little Dutch Boy with my finger over the hole till tank drained down. DW thought it was the funniest thing she had seen in a while. Glad she did not have phone or it would have been on Youtube.

Re: Black tank mystery

Reply #49 –
Quote from: steve31 –
I to have made that modification...
If you are talking about the lubrication mod in the video linked above, I don't understand how any "stuff" could come out the drilled hole.  That hole is up in the "top" section of the valve housing where the steel shaft goes up and down.  That area of the valve is outside the two seals that surround the moving blade.  The seals keep all the liquid from escaping around the blade as it moves up and down.  Unless the blade seals are damaged and leaking badly, there should be nothing except the grease that was injected, and no pressure, in that part of the valve.

Re: Black tank mystery

Reply #50 –
This version of the "valve lube mod" makes more sense to me.  In this case, the RV owner is filling the empty void in the valve housing with liquid lubricant.  With the void full of lube, every time the blade is opened and closed, both faces of the blade will be treated to a thin coating of liquid lube.  This will ease the movement of the blade through the tight rubber seals that surround the blade on both sides.  It will also lubricate the steel shaft as it is moved up and down through the shaft guide.

Using a liquid lube seems more logical (to me) than using a semi viscous white grease.  Of course, I've not actually tried either mod, so...

https://www.youtube.com/watch?v=2GDErKY05-8

Re: Black tank mystery

Reply #51 –
How about one of those cheap plastic syringes filled with vegetable oil?

Re: Black tank mystery

Reply #52 –
I took out the fiberglass wall between battery bank and drain valves. Attached photos of open and closed.

I also put snake up drain with black tank supposedly open but hit a wall. So I think the gate is not opening.

I like idea of lubrications- Oh if it could be that simple! Just don't know where to begin.

Thinking of getting some sewer company to drain the tank through the toilet before embarking further.

I appreciate all the conversations and videos. Truly.

Susan

Re: Black tank mystery

Reply #53 –
When I changed my black tank valve, I wished there would have been a way to drain mine first. It wasn't pretty to say the least. The cost to have it pumped would have been negligible.

Larry

Re: Black tank mystery

Reply #54 –
Quote from: Susan –
I took out the fiberglass wall between battery bank and drain valves. Attached photos of open and closed.

I also put snake up drain with black tank supposedly open but hit a wall. So I think the gate is not opening.

I like idea of lubrications- Oh if it could be that simple! Just don't know where to begin.

Thinking of getting some sewer company to drain the tank through the toilet before embarking further.

I appreciate all the conversations and videos. Truly.

Susan
If you look at the pictures in Chuck's reply #13 link, I believe you could do the same thing after getting the sheet metal out of the way of the valve. You will be replacing it anyway.

Re: Black tank mystery

Reply #55 –
Susan,

You'll have to excuse us - we are bad around here about going off on tangents in these threads.  Like talking about lubing the dump valve, which is of no help to you at the present time.  But we mean well, and a lot of times the digression brings up some very useful info.  But to get back to your problem...

Like Chuck (craneman) says, I think your best course of action is to follow the procedure shown in the link below.  Looking at your recent photo, I agree with Red Tractor when he said he thinks the electric part of your dump valve has been added on to a standard manual valve.  If the metal parts of the valve are unbolted and removed, then I think you will be looking at the same valve as shown in the photo below.  The metal rod will probably pull out of the top of the valve when the metal frame is removed, because we think the rod has separated from the sliding gate.

NOTE:  I'm still trying to think this through in my head.  If you try to remove the metal framework and the steel operating rod does not want to pull easily out of the top of the valve, STOP THERE and get back to us.  If that happens it might mean the rod has NOT come loose from the top of the blade, and we will need to reconsider this whole plan.

Once the metal parts are out of the way, the idea of the "fix" is that you (or someone) will carefully cut the top section of the valve off with a saw or a Dremel tool with a cut-off wheel.  When the top of the valve is removed, then it should be possible to grab the actual sliding gate with Vice-Grip pliers and carefully pull it up, which will open the valve and let the tank drain.  You don't want to pull the gate up too far, or it will come completely out of the valve body resulting in a small geyser.  Try to just inch it up slowly until about 1.5" of the blade is exposed.  This should open the valve enough to let the tank drain.  Looking at the photos in the link will help clarify this explanation.

Waste valve handle and rod pulled out of the valve - Airstream Forums

If you wish to get the tank contents sucked out by a septic tank service truck before attempting this operation, that sure wouldn't hurt anything.

When removing the metal and electric parts of the valve, try to pay attention (make notes) to how it is attached.  Once you finally get a new dump valve in place, you will want to reinstall the metal frame to (hopefully) restore the electric valve operation.

Re: Black tank mystery

Reply #56 –
Any news Susan?