Index Home About Blog
From: John De Armond
Newsgroups: rec.outdoors.rv-travel
Subject: Re: Oil in propane
Date: Fri, 11 May 2001 14:32:48 -0400

David Lippincott wrote:

> Here's an odd one.
> I'm getting oil out of my propane supply on my class A.  Anybody seen
> this?
> To make a short story long, I've got an extend-a-flow hooked to a small
> bbq.  I found oil coming out of the orifice of the regulator on the
> bbq.  With just the regulator in hand, hooked up and spewing gas, I get
> sizeable quantities of a yellow oil, similar in texture to 3-in-1
> spitting out of the regulator.  Enough to pretty much soak a paper
> towel.  The oil is definitely coming out of the propane and is not
> contamination from the bbq.

Several possibilities come to mind.  If the oil is REALLy stinky,
it's probably the mercaptin oil added as odorant.  There was a wild
story going around a couple of years ago, hyped by the media, that
the odorant was expiring in propane which would produce stink-free
propane and kill thousands of women, children and baby harp seals.
I've noticed a LOT more odorant in my propane since then.  I'm
surprised to hear about this in a new tank but if the filling
station takes suction from the low end of the tank, I suppose it
could pump excess odorant into your tank.

Second possibility is cutting oil.  Is there any black iron pipe
between your hose and the tank?  Plumbers are real bad about not
cleaning out all the cutting oil after threading black iron.  It
could also have come from new black iron plumbing at the fill
station, at the propane supplier or anywhere else in the chain.
Propane is an excellent solvent so it will bring along whatever it
encounters in the piping and tankage system.

Finally, it could be mill oil left on the inside of the tank by the
mfr.  Normally the metal is cleaned but this one could have been

I'd have to see the oil to speculate in any greater detail.


From: John De Armond
Newsgroups: rec.outdoors.rv-travel
Subject: Re: Oil in propane
Date: Sat, 12 May 2001 01:55:30 -0400

David Lippincott wrote:

> The oil is coming either directly from the tank or from the hose since
> the hose is practically connected directly to the tank.  The
> extend-a-hose folks swear they don't use oil and I can believe that.
> Can't see inside the tank.  Even if the tank were contaminated, how
> would the oil get into suspension and out the vapor valve.  I'm
> presuming the vapor valve pick-up is in the top of the tank above the
> liquid level.  The oil would have to be in suspension in the gas.

I could speculate on transport methods but you're seeing the
existence proof that it happens :-)  The proof is dripping out the

> Hard to believe the oil is coming from the rubber in the hose as it isn't
> always connected and is approved for this application.
> Somebody suggested it might be the odorant.  Smelled it and it smells a
> little like gas, but not over powering as I would expect from raw
> odorant.

Maybe you got some of that rare stuff that quit stinking....

> Stan - what RV do you use?  I find it interesting that 3 of us have the
> same problem.  It's a little more that a curiosity to me as it made a
> mess of the bbq, dribbled in the storage bay, caused the bbq to stutter
> and flare, and the extend-a-flow guy says the stuff hardens up and will
> kill the regulator.

This is way out of line.  The little bit of odorant I've seen in
tanks where I've removed the valve is literally a couple of drops.
You almost surely have a contaminated tank, probably because it was
not properly cleaned during manufacturing.  At a minimum, I'd want
the tank dismounted and de-valved, solvent flushed, dried, purged
and refilled.  A new tank might be in order.  I'd also want a new
regulator and at least have the house plumbing inspected for
contamination.  If this oil goo has gotten in the black pipe, it
might take weeks or months to get to the appliances but when it
does, all sorts of problems will develop, not the least of which is
clogged pilot orifices.

This is something the dealer ought to be dealing with and Safari
paying for.


From: John De Armond
Newsgroups: rec.outdoors.rv-travel
Subject: Re: Oil in the propane?
Date: Thu, 11 May 2006 01:08:24 -0400
Message-ID: <>

On 9 May 2006 02:20:15 +0200, "Jon Porter" <>

>I have one of those 20# propane tanks for the grill that is from those
>expchange places where you trade the tank. The regulator on the grill hums
>sometimes so I checked it out. What I discovered at the screw in connection
>was an oily film that I'm sure isn't from the meat on the grill. I also
>recall oil being in the old regulator on my Class B when it was replaced a
>few years back, quite a bit drained out. Is it normal for there to be a bit
>of oil in the propane?

Yup. Considering how good a solvent propane it, it's inevitable that
some oil will end up in the end product.  Some from an imperfect
process of refining.  Some from the equipment that handles the stuff
from the refinery to your tank and a little from the odorant.

FWIW, I recently opened the 500 gallon tank at my cabin to replace the
level gauge.  This tank has been in service at my cabin for >35 years
and it was used when my mom bought it back then.  It contained several
gallons of clear, very stinky oil.  I pumped it out into a container.

Surely it has some practical joke value :-)


From: John De Armond
Newsgroups: rec.outdoors.rv-travel
Subject: Re: oil in propane
Date: Thu, 10 May 2007 03:18:58 -0400
Message-ID: <>

On Wed, 09 May 2007 21:43:45 GMT, GaryO < @ . > wrote:

>I know this has been discussed here before, but I don't know if there
>was a definitive answer, or just guesses...
>The other day when firing up the grill, I was having difficulty
>getting it to light, and heard an unusual sound.  Looking at the
>orifice where it connects to the burner tube, I could see a stream of
>liquid shooting out.  :-(  Shutting off the gas, I disassembled the
>grill valve from the burner tube and drained out 1-2 tablespoons of a
>clear to pale yellow oily liquid.  The residue was flammable, as it
>did burn off once I got the grill lit - a thick black smoke.

It's oil and sometimes a little water.  I've never opened up a used propane tank but
what there wasn't some of that in there.  I recently opened my 500 gallon tank at the
cabin to repair the level gauge.  This tank's been in operation since the 60s and
contains probably 5 gallons of oil. Some of it probably tramps over from the refinery
and some probably comes from pumps that handle the stuff between here and there.  It
almost always has mercaptin dissolved in it so it does stink.

My major question is, how did the oil get to the regulator and gas system?  Unless
the tank was tipped over where liquid propane could flow out, I can't imagine a

In any event, it won't harm the hoses or regulator.  The hose has to be liquid
propane resistant and that is a much stronger solvent than the oil.  If you have an
air compressor, disconnect the line from the regulator and blow out the line so that
another blob won't come through.  Other than that, don't worry about it.


From: John De Armond
Newsgroups: rec.outdoors.rv-travel
Subject: Re: oil in propane
Date: Fri, 11 May 2007 06:37:55 -0400
Message-ID: <>

On Thu, 10 May 2007 15:31:11 GMT, "Nate" <> wrote:

>Would it be a good idea once in a while to flip the tank on it's side and
>let it sit and then after a while let the gas out, along with the
>liquid...just as a precautionary maintenance item?

Nope. When there is propane in the cylinder, propane and the oil are mixed together
completely.  Propane is an excellent solvent for oil. The only time that the oil can
be poured out is when the tank is empty.  Otherwise you just spray a mix of liquid
propane and oil.

The only time I'd even worry about it is if I owned the tank. otherwise, for a 20
pound tank, just trade it in and let the gas company worry about it.


Index Home About Blog