Skip to main content
Topic: Vegetable Oil to lubricate Black and Gray water tank valves (Read 7720 times) previous topic - next topic

Vegetable Oil to lubricate Black and Gray water tank valves

Somewhere I read the suggestion to pour vegetable oil into the black water and grey water tanks when they are empty to lubricate the valves used to empty these two tanks.  I do not remember where I read it and was wanting to determine how much vegetable oil should be used in each tank.

Does anyone here use vegetable oil to lubricate these waste valves?  If so, how has it worked for you and how much do you use in each tank?

Thank you.
Morris and Janice
1997 U270 36'

Re: Vegetable Oil to lubricate Black and Gray water tank valves

Reply #1
We use plain old corn or mixed vegetable oil ... wherever it is good and cheap.  I wait until the tanks are totally empty, pour a cupful or so into each tan via the commode and which ever sink is closest to the grey tank, and wait a bit for it to settle down to the bottom and the valve.  Then we pull each valve a few times to lubricate the action.  You can absolutely feel the difference when the oil begins to cover the surfaces of the valve itself.  It is not really magic, but it is cheap, eco-friendly and it helps. 
Carol & Jeff Savournin
Usta have a '93 U225 36', Usta have a '95 U320 40', Usta have a '02 U320 40'
Usta have a 2006 Born Free, Usta have a 2011 Phoenix Cruiser
Usta have a 2012 Jeep Wrangler Unlimited 4dr
"Your time is limited, so don't waste it living someone else's life."  Steve Jobs

Re: Vegetable Oil to lubricate Black and Gray water tank valves

Reply #2
I think the commercial product for lubing the valves is made of coconut oil if I remember correctly.  Veggie oil should be just fine.
1994 U225
build #4514

Re: Vegetable Oil to lubricate Black and Gray water tank valves

Reply #3
We do the same thing that the Savournin's do.  No doubt they borrowed it from us :).
George Stoltz.  Retired from full-time living in a great Foretravel and now are back to living in a traditional sticks and bricks in Florida.

Re: Vegetable Oil to lubricate Black and Gray water tank valves

Reply #4
Imitation is the sincerest form of flattery George, and somebody mentioned dumping a bottle of Dawn down the drain, which has me visualizing the coach filling up with soap suds as you drive down the road  :))
1996 U270
Build #4846

Re: Vegetable Oil to lubricate Black and Gray water tank valves

Reply #5
Yes, I use Dawn liquid detergent which does multiple duty...it lubricates at the same time that it loosens "stuff" and cleans out "stuff"...plus it has the added benefit of odor cleansing...if ya know what I mean.  And, it is just as slippery as veg. oil.  Also oil attracts stuff sticking to it and gumming up.  Whereas detergent is very water soluble and dissipates easily leaving very little trace behind to create sticky "stuff".
 
Oh, I forgot, I've never had it suds up out of the coach.  But, if it did, then it would also lubricate & clean other "stuff" as well.
 
p.s.  Use a bit of it at the stool seals.  It works there as well... ;D
Peter & Beth Martin
No Forrest? What have you done?
MC# 15890 until Dec 2016; FMCA #F329677
Cincinnati, OH

Re: Vegetable Oil to lubricate Black and Gray water tank valves

Reply #6
I agree with Peter, Dawn or some similar product might be better.  Vegetable oil can cause problems for septic systems and many, especially rural RV parks, are on them.  Vegetable oil is lighter then water and will tend to float on top of the septic tank fluid while a detergent is readily soluble in water and all are now biodegradable.  However, detergents probably don't have much of a lasting lubricating effect because they are so soluble. 

Here is another reason not to use cooking oil, or any oil in your waste tank.  By floating on the top of the liquid in the black tank, it cuts off oxygen to aerobic bacteria (the "good backeria" in your tank smell-wise).  Pat found this quote on the ECO-SAVE site that comes from a paper published in the Escapees Magazine by Phred Tinseth (published in 2000).

"More no-nos listed separately because so many RVers use them in homemade concoctions; pine oil (which deteriorates gaskets), automatic dishwasher detergent (extremely caustic), mineral, coconut, or cooking oils (which really won't lubricate valves and seals, but will just float on the surface and keep air from getting to the good bacteria), yeast (which will promote bacteria, but you will have to use so much that you'll have a tank full of goo)"

see Macerators and Other Sewage Stuff by phred
The selected media item is not currently available.
George Hatfield

  Never ever use World Line Motors of Nacogdoches for service!

Re: Vegetable Oil to lubricate Black and Gray water tank valves

Reply #7
Have read in several places that fabric softner will work in these ways also?  Anyone heard of that option?  ???
Loving our gently used
1998 U295 3600 WTFE
Bill and Ricki

Re: Vegetable Oil to lubricate Black and Gray water tank valves

Reply #8
George said: "Dawn or some similar product might be better".

I have been using peanut oil (suggested by Barry and Cindy) as well as Dawn and here is what I have found: When peanut oil (or any other vegetable oil) is used first, as described previously, and allowed to coat the valve by moving the valve up and down a few times, very little of the oil is left to float in our holding tank. The valve then works easily. However, regarding Dawn: Remember, it is not a lubricant, it is a detergent that cuts (dissolves) grease and oil. It will not lubricate the valve; rather, it fairly quickly removes the lubricant-action of the vegetable oil.

While using both peanut oil and Dawn, I found my black tank valve became sticky within a week or two. When using the oil alone, the valve movement stays smoother much longer. At each flushing of the black tank I add about a cup of the oil, but use Dawn less frequently. My gray tank valve has been in for more than 6 years and never has needed additional lubrication. Apparently there is enough oil in dishwater to facilitate the valve movement, the "stuff" in the black tank is really abrasive.

Previous Thread
Vegetable oil in black tank to lube valve
Don Hay
'92 Grandvilla, U-280
The Hayfever Express
Build #4055
'97 GEO Tracker
Life is like licking honey off a thorn.

Re: Vegetable Oil to lubricate Black and Gray water tank valves

Reply #9
Have read in several places that fabric softner will work in these ways also?  Anyone heard of that option?  ???
The "Fabric Softener" is probably a reference to Liquid Calgon water softener.  There is a "recipe" for a periodic cleansing of the tanks that calls for adding about a cupful of Liquid Calgon laundry additive and a half cup of Dawn to the tank with a gallon or two of warm water just after emptying it and just before taking to the road.  slosh, slosh slosh ... when you get to your new destination, add more water and dump again to get out the residue that can build up in the bottom and sides and does not leave with just regular dumping.  As for the vegetable oil in the tank for lubricating the valves, I do not believe it is enough to "blanket" the contents and cut off oxygen, and you only need to do it occasionally.  There is probably more "oil" in soaps and shampoos. 
Carol & Jeff Savournin
Usta have a '93 U225 36', Usta have a '95 U320 40', Usta have a '02 U320 40'
Usta have a 2006 Born Free, Usta have a 2011 Phoenix Cruiser
Usta have a 2012 Jeep Wrangler Unlimited 4dr
"Your time is limited, so don't waste it living someone else's life."  Steve Jobs

Re: Vegetable Oil to lubricate Black and Gray water tank valves

Reply #10
"Camco TST Drain Valve Lube

Lubricate plumbing lines while you drive. Prevents sticking valves with COCONUT OIL, making equipment last longer. Recommended for all applications: waste holding tanks, black and grey water systems."

Knew I saw that somewhere.
1994 U225
build #4514

 

Re: Vegetable Oil to lubricate Black and Gray water tank valves

Reply #11
We buy a 45 oz bottle of the cheapest laundry soap we can find ($2.00 at Walmart or Family Dollar) and put a cap full down the black tank each day.  Makes the valve run smoothly and nothing stays behind. :))
Dave and Nancy
1999/2013 U270 36' Xtreme
Motorcade # 16774
2013 Subaru Outback
KD0NIM