Black Water Tank Valve

[8e3k0]

Opened up part of the under belly to take a look at the black water valve as the valve closes from the remote stations but does not hold when in the closed position. Evidently there is something in between the valve and its body not allowing it to close completely. This is the first drop frame model (2009 3400RL) and I noticed that the three inch line comes out of the tank and has the valve near the tank, left side of rig. From there the pipe has a 90 and runs to the center of the rig where there is a 3 inch "Y". From this "Y" the pipe runs to the rear with another 90 and out to the side of the rig. Also from this 3 inch "Y" is a 3 in pipe that runs to the right hand side of the rig. Where does this pipe go/enter as it cannot be from the toilet being on the drain side of the black water valve? I couldn't get enough enough of the belly cover down to see this side of piping. Any ideas or experiences would help. Will try and back flush 3 inch to see if that will help the black water valve. Not the easiest place to work under!! Thanks for any suggestions and advice. Ellis

[8e3k0]

Was able to access and view the right hand side of the underbelly and found another 3 inch valve on the right side (passenger side) of the rig that ties into the 3 inch "Y" drain assembly. So now the conclusion must be that I have a 3 inch black valve and a 3 inch grey water valve on the front tanks?? The right side of the rig must hold the black water tank and its valve not the left side (driver's side)?? The 1 1/2 line that ties into the 3 inch must be a vent to roof? Sure be nice to have drawings or prints as per construction!! Any views or experiences?

[bigskyjimmy]

That thing that is stopping your valve from closing all the way is called Toilet paper I have taken my black valve apart many times on my 3 5ers and cleaned out the jammed tissue and lubed the knife valve in there(I just did it a week ago on my new one),the black tank valve on your 3400rl is I think on the same side as my old 2012 3402rl and my new one it is the one on the passenger side(curb side)it is no big deal to take it apart (4 bolts and nuts)just takes a little time and make sure you give it a good flush a drain first or things will get messy and also when you put the valve back in be sure the gasket stays in place

[1retired06]

[quote]Originally posted by bigskyjimmy

That thing that is stopping your valve from closing all the way is called Toilet paper I have taken my black valve apart many times on my 3 5ers and cleaned out the jammed tissue and lubed the knife valve in there(I just did it a week ago on my new one),the black tank valve on your 3400rl is I think on the same side as my old 2012 3402rl and my new one it is the one on the passenger side(curb side)it is no big deal to take it apart (4 bolts and nuts)just takes a little time and make sure you give it a good flush a drain first or things will get messy and also when you put the valve back in be sure the gasket stays in place
[/quote

X2!

[DuneBuggyBuilder]

Having done this just a few weeks ago, it isn't too bad. There are two tanks running longitudinally in the dropped frame section. The galley tank is (usually) aft and running crosswise. The galley tank uses the smaller drain pipe, the black and shower tanks use a 3" drain pipe. My black tank is on the street side. But yours could be on the curb side - who knows what all Montana is capable of. Check in the passthru basement storage area and see where the toilet down pipe goes.

Flush the tank numerous times before doing anything. Drop the front end below level to prevent any leakage back through the opening once you remove the gate valve. The valve is easy to remove but difficult to re-install with the seals positioned properly. I cut the 3" pipe downstream of the "Y" and removed about 1" of pipe. This allows some slop to move the waste pipe and properly position the gate valve and the seals back into the tank fittings. Get a 3" No Hub plumbing fitting to bridge the cut drain pipe. This also allows some flexing once everything is back together and may avoid the tanks cracking somewhere down the road.

You can order new seals from Amazon to ensure no leaks and a tight seal against the valve's blade.

[bigskyjimmy]

yeah That is a good Idea and I should have done that many times but on my black tank valves there is enough space to put it back in but yeah that would make it easy for sure

quote:Originally posted by DuneBuggyBuilder

Having done this just a few weeks ago, it isn't too bad. There are two tanks running longitudinally in the dropped frame section. The galley tank is (usually) aft and running crosswise. The galley tank uses the smaller drain pipe, the black and shower tanks use a 3" drain pipe. My black tank is on the street side. But yours could be on the curb side - who knows what all Montana is capable of. Check in the passthru basement storage area and see where the toilet down pipe goes.

Flush the tank numerous times before doing anything. Drop the front end below level to prevent any leakage back through the opening once you remove the gate valve. The valve is easy to remove but difficult to re-install with the seals positioned properly. I cut the 3" pipe downstream of the "Y" and removed about 1" of pipe. This allows some slop to move the waste pipe and properly position the gate valve and the seals back into the tank fittings. Get a 3" No Hub plumbing fitting to bridge the cut drain pipe. This also allows some flexing once everything is back together and may avoid the tanks cracking somewhere down the road.

You can order new seals from Amazon to ensure no leaks and a tight seal against the valve's blade.

[denverdale]

I have a 2014 Montana 3150RL. The black tank gate valve leaks so every time I set up at a new location, I have to be very careful removing the cap on the end of the drain.
Does anyone know the location of the valve relative to the overall trailer? I think I may just install a new valve at the end of the drain and not worry to much about the valve near the tank.
I thought I had read somewhere about a known issue with these valves. Does anyone know about that?
Dale

[pineranch]

Most experienced RV'ers (those that had your problem) have installed a master shutoff valve near the end of drain.
Mike

[DuneBuggyBuilder]

Read my previous post re the location of the valve. It is easy to access near the back end of the dropped frame. I would strongly suggest you replace the black valve (in addition to adding a gate valve). Allowing the liquids to run out of the black tank but leaving the solids is a recipe for future problems. You need the volume of the liquid to flush the solids when you finally dump. The gate valve is more for catching leftover yuck left in the drain pipes after the valves are closed. As you drive down the road that stuff all collects at the drain cap and is just waiting to surprise you when you remove the cap. The gate valve stops that!

[Clemson1881]

As stated earlier install a twist on gate where your hose connects. That will stop all leakage from the black tank gate not closing. Start using two capfuls of liquid Calgon water softener in each black tank uses. After 10-20 cycles your valve will likely self clear and start working again. Continue to use the Calgon and your problems will likely be over. Keep the twist on valve installed for insurance.

[Rondo]

I agree with Greg(Clemson1881. I've installed the second twist-on gate at the end of the drain outlet. I also use Calgon liquid but don't do it every dump or drain. I also use Cascade with Dawn powdered dishwasher soap in the black tank whenever I drain the black tank and head down the road to the next destination. I do put about 5-6 gallons of water into the tank so the Cascade sloshes around while going down the road. Oh, I use it in both gray tanks also at the same time and it keeps them clean of oils and soap scum, too. During our sitting at a campground for a week or more I use Happy Camper and it works well to help dissolve the toilet paper and other solids while sitting there. Oh, I also have a twist on tank backflush elbow I use to backflush the black tank from the outlet side and it gets a lot more of the gunk out of the black tank than the OEM backflush nozzle in the tank.

[Art-n-Marge]

In my over 10 years of RVing and the past 3 years of fulltiming, I have avoided any TP problems by making sure the flushing process includes plenty of water. Not just for ensuring no clogs, but reading the container labels for the chemicals I use, it's suggested to use plenty of water. I recommend a 5 count for liquid waste and a slow 10 count for solid waste. With the sucky water pressure it doesn't seem like a lot even living in California under drought conditions but it's been enough to prevent this problem. Don't forget to tell this to your guests, too.

After I drain my black tank, I follow the chemicals with about two gallons of water to start the dissolving process. I dumped a gallon of water into the bowl so I know how much is a gallon, then after I dump the tank. I backfill the bowl twice along with the chemicals (your chemicals may vary). So far, so good.

I was lucky enough to hear this suggestion from an old-timer who helped me with the PDI when I bought my Monty. He was very knowledgeable and experienced, so I heeded his advice and I've had NO problems.

[CORattler]

If you use drop in tank packets they too could be the problem (it was for me). Symptom was that the valve handles would not close all the way and would partially back out. The packet was jammed in between the seals by the knife valve.

quote:Originally posted by bigskyjimmy

That thing that is stopping your valve from closing all the way is called Toilet paper

[rohrmann]

We had a problem with our black tank valve, early on, and it turned out that we failed to educate a relative that stayed with us a couple of days, and she tossed one of those wipes down the toilet, and the weave of the wipe hung up on the fitting at the valve, which required a total disassembly of the valve. When they made repairs, they had cut the 3" line away from the elbow, and put a rubber repair coupling get the cut, which adds a little flexibility to the lines. Have not had any trouble since.

[Bill.vannuys]

Enjoyed reading all the tips here and finally tackled my "never functioning correctly" black valve tonight. My valve would seep fluid and never would close all the way. Also, it's always been very difficult to close and then would back out a little.

Paid a dealer to check it once right after we bought it brand new; dealer disassembled and claimed toilet paper was clogging it. Might have been, but it didn't make it work any better.

So, tonight I dropped the belly cover and put on the disposable gloves! I had no problem removing the 4 bolts and valve once I got my 6'3", 240 pounds wedged in place. When I removed the valve there was no toilet paper or other () obstruction. The problem seems to be the deformed gaskets wedged into the valve groove. It was easy to see where one gasket was obviously catching the blade and preventing it from closing all the way or sealing. The gasket is permanently deformed (I tried to make it look new again- failed!).

I decided there was no point in trying to make the deformed gasket work, so I will go in the morning to one of the RV dealers in Kansas City to get new gaskets rather than have to do this again. I would order from Amazon, but need to leave in the next day or so for Kentucky - waited until the last minute to do this job.

The valve works great with no gasket in; closes all the way and smooth.

Expect the valve will work well with good gaskets and hopefully not refuse to close all the way like it has since new.

QUESTION: Should I lubricate the valve or gaskets with something? Vaseline?

Thanks for any input.

[richfaa]

We do pretty much what Art does that is use plenty of water , dump often and flush well. We rarely use chemicals except when it is very hot. We are with full hookups 98% of the time so we can do this. It many appear to be overkill but we have learned over the years what needs to be done to these tanks.

[bigskyjimmy]

QUESTION: Should I lubricate the valve or gaskets with something? Vaseline?,,,,,,,, Yes Bill I did use plumbers grease on the blade when I cleaned my valve out and put new cables on ,don't know if I had too but anyway after 3 months now the new cable and cleaned valve is as smooth as silk

[Bill.vannuys]

Jimmy,
Thanks! Got the wife returning home with plumbers grease right now!!!

Had to drive an hour each way to get the gaskets; the first (and closest) Camping World dealer had no clue (and no qualified parts person -scary when I know more than the dealers staff). Finally, 3d RV dealer provided excellent service.

Interesting that you replaced the cable. I thought I would have to also, but the valve works very smoothly without the gaskets which tells me my problem is not with the cable; must have been the jammed gasket.

Well, excited to get it back together, so on with the gloves and wedge myself back under the trailer[

Thanks again for your help!

[Bill.vannuys]

Just finished installing the black tank valve gaskets (new!) and re-assembling the underbelly. Had my wife test the handle in the convenience center several times while I was still at the valve and it works great! I opened and closed it also after I closed the belly; NICE!

I used the plumbers grease BigSkyJimmy recommended. Definitely makes it operate smoother.

The handle closes all the way for the first time; even when I bought the Montana New last summer, the valve never worked correctly. Should have done this a long time ago! Instead, I left it on my deferred maintenance until now.

Again, I have never had a problem with the toilet paper clogging things, so I thought it would be unusual that "all of a sudden" it would start happening. I also fill the tank with lots of water as suggested here - especially before dumping.

Thanks again for all the information and responses on this thread.

[bigskyjimmy]

YAHOO!! glad you got it done and working,yeah it is not such a hard job just time consuming and like ya said it is hard for us old Big Dudes to get under there