Black Tank Issue - Dodged This One!! - Montana Owners Club

Camp CA · 08-13-2020, 03:43 PM

Went to dump a full black tank (after back filling with water through the flush connection) after a week of camping and found the black tank valve stuck!! First time in 16 years and on a relatively 2020 trailer. My wife immediately called our dealer's service department 200 miles away and were told to get a pair of pliers (channel lock in my case) to grip the stem and pull the valve with the pliers and guess it finally the valve opened. We were so relieved as we were ready to drive 200 miles to the dealer in Pismo Beach, CA. Lots of possible causes like tp stuck in the valve gate, rusty valve stem, etc. I think it was rusty valve stem due to flush water leaking onto it. So I installed quick disconnect leak-tight flush hose connections to mitigate water leaking onto the stem AND sprayed some lubricant on the stem then exercised it a few times. Will make that part of operating procedure AFTER we pre-fill the black tank with water AND BEFORE we use the toilet. Will also replace the valve stem, hopefully with a stainless steel stem (and under warranty this winter when we return to the dealer). Any other suggestions to mitigate from happening again?

This thread discusses a similar issue that might be of interest: https://www.montanaowners.com/forums...p/t-60762.html

Dave W · 08-13-2020, 04:36 PM

Possibly a wad of TP stuck in the seals. I doubt that there is any rust - the solid, single strand cable, if it's a Varterra is non magnetic stainless while the ferrule at the handle is slightly magnetic.

I buy a gallon jug of the cheapest Walmart or similar vegetable oil. About 1/3 goes in each tank along with a gallon or so water to free up the seals. The handles will then pull pretty easily - until the next time.

Camp CA · 08-13-2020, 04:46 PM

Cheap vegetable oil......OK I will try that in each gray and black tank on our next trip. Might avoid replacing the valve stem. Thanks for the tip!!

mhs4771 · 08-13-2020, 05:34 PM

Have a question about the oil:
If I remember correctly from School (long time ago) that oil and water don't mix and that the oil will float on top of the water.
If that is true, how much good does the oil really do??

Camp CA · 08-13-2020, 06:22 PM

Forgot to mention that I came up with 2 options if I could not get the black tank valve open........drive 200 miles to my dealer OR hire a septic pump out company and I could not find one that would pump out the holding tank through the toilet. Fortunately., the valve finally opened.

Montana Man · 08-13-2020, 08:20 PM

I did the vegetable oil trick. After draining the tanks, pour in a bit and let it flow to the valve then open and close them a couple times. The rubber seal gets coated and makes the operation smoother. I suspect with the coating of oil the components will repel water long enough until the next drain and treat evolution.

With regard to the cable pull valves, be prepared for trouble. They just aren't engineered for durability.

Dave W · 08-14-2020, 04:42 AM

Quote:

Originally Posted by mhs4771

Have a question about the oil:
If I remember correctly from School (long time ago) that oil and water don't mix and that the oil will float on top of the water.
If that is true, how much good does the oil really do??

Yep, oil floats on water but if it's empty - no water to float on and why I add a couple gallons of water to that empty tank and allow it to float and therefore reach the valves. With a prtially or full tank, that trick may or may not work though if traveling, that oil will slosh around and may (or may not0 coat those sticky neoprene seals though will when opened, regarless but by a somewhat lesser amount.

For the SS pull line, I use a penetrating oil like PB Blaster and the supplied straw at the handle and try to spray it down the pull line. WD-40 today vs years back is, IMO, now about useless. A note - the Valtera is not cable but a flexible single wire . The LaSalle-Bristol valves - not sure but believe they are stranded cables.

Works for me, others - worth a $5.00 gallon of veggie oil rather then hors of lying on your back, dropping the belly cover and replacing two $50 valves that there really was little problem with other then sticky seals or a pull cable that was poorly routed (as mine were on our current Montana)

jcurtis934 · 08-14-2020, 01:25 PM

The LaSalle Bristol valves use a solid wire cable and bends add more resistance to operation...especially when a vendor bends the cable into tight bends to make it suitable for shipping in a small box.

dfb · 08-15-2020, 10:03 AM

I used a slide hammer... It worked...

Camp CA · 08-16-2020, 11:20 AM

Quote:

Originally Posted by dfb

I used a slide hammer... It worked...

Can you recommend a slide hammer for an rv dump valve?

Thanks to everyone's recommendations above. I will add oil to all 3 empty tanks prior to my next trip in September.

Leftie Canuk · 08-16-2020, 07:00 PM

Quote:

Originally Posted by Camp CA

Can you recommend a slide hammer for an rv dump valve?

Thanks to everyone's recommendations above. I will add oil to all 3 empty tanks prior to my next trip in September.

I decided to avoid the push/pull cable issue by replacing my black tank valve with an electric valve. So far so good. It was not that tough, and the valve assembly has a manual option in case there is an electrical issue. I realize your rig may be quite new, but my experience with another brand was that cables are not very well suited to operating the blade valves in RVs. Eventually I fabricated push-pull rods for the other RV, but this time opted for an electric version.

dfb · 08-16-2020, 07:37 PM

Quote:

Originally Posted by Camp CA

Can you recommend a slide hammer for an rv dump valve?

Thanks to everyone's recommendations above. I will add oil to all 3 empty tanks prior to my next trip in September.

Just the kind any auto place should have. It has a threaded end. I used an allen with a 90 degree bend. I place the allen over the Tank
handle and slide the hammer back a few times until the valve breaks loose.. .

mleeder · 08-19-2020, 02:57 PM

Had the same issue. It was rust and gunk in the line right up front. I ended up replacing the valve with an electric Valterra just for the black tank. What I recommend is replacing the cable with a new one and than keep it lubed with silicone or cable lube. Do not use WD40, it gets gummy over time. I don't actually recommend the electric valve because I had it go out under warranty, valve motor failed.
Also most people know you can actually go underneath to the valve and open it manually. If all holds true with the models, It is on the passenger side near the drop down.

Camp CA · 08-19-2020, 03:17 PM

Thanks for all the great advise!! Put 2 quarts of vegetable oil into the holding tank, cleaned / polished the valve stem and sprayed it with silicone spray and do this regularily, espeacilly before use. I will also cliimb under the rig to see if I can access the valve. If I do not feel comfortable replacing the valve and/or stem I will have the dealer replace while under warranty.

Scootsk · 08-19-2020, 03:50 PM

Same thing happened to me on a 6 month old trailer. I tapped the handle inward with a hammer and it freed up. Sprayed some silicon lube on the shaft and so far so good.

deb50jean · 08-19-2020, 04:07 PM

Don't want to seem ignorant but our actual pull handle is very difficult to pull and doesn't completely stay in when pushed shut. Will silicone work on that situation? I'm an older woman with three pretty able bodied daughters but I'm not sure they would have a clue where to do any of this under the camper. Should I try the vegetable oil also - our camper is permanently parked? Thanks for any help!

Eddiea · 08-19-2020, 04:43 PM

Quote:

Originally Posted by deb50jean

Don't want to seem ignorant but our actual pull handle is very difficult to pull and doesn't completely stay in when pushed shut. Will silicone work on that situation? I'm an older woman with three pretty able bodied daughters but I'm not sure they would have a clue where to do any of this under the camper. Should I try the vegetable oil also - our camper is permanently parked? Thanks for any help!

I poor a big cup full of Dawn blue soap down toilet and let set over nigh, seems to help, it gets into seals and helps lubricant

MuddyPaws · 08-19-2020, 08:18 PM

If the seals are made of urethane, like the seals in most RV toilets, vegetable oil will damage them.

A silicon based lubricant is the way to go. I use pool lube but there's no way to get it into a gate valve that I know of.

Buckfisher · 08-19-2020, 09:33 PM

I use dawn dish soap. Haven't had odor problems and the valves operate smoother. Use it in all 3 holding tanks. Pour it in after dumping and with valves closed. Maybe up to a half cup. Add a little water. You can add more dawn later if you start getting some odor. I usually don't need any other tank treatment unless the temperature gets around 95 to 100 degrees. Works for me!

David Leak · 08-20-2020, 11:33 AM

Be careful about adding any kind of oil to the holding tanks if you value your tank level sensors, or the septic system where you are staying.
The oil will coat the inside of your tank and may cause problems with your tank level indicators, and problems later on for your campgrounds host trying to get the oil out of there septic system.

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