I need to spray used oil on a number of truck frames etc.
I would like to know what is a good solution, preferably compressor
driven, that would make a good spray pattern and preferably not too
I am not interested in opinions about advantages and disadvantages of
used oil spraying, I just want to know how to spray it.
Ignoramus3828 fired this volley in
Find an old DeVilbiss (or other brand) air-powered "airless" sprayer. I
have one for painting. It is a superior sprayer of paint, even of high-
viscosity. I have absolutely NO doubt it would spray motor oil equally
It looks like a 'paint canister' of the sort for air-spraying, except
with a piston mechanism on top to do the pressurization of the fluid,
rather than relying only on air pressure. Like motorized airless
sprayers, it can produce many hundreds of pounds of fluid pressure,
instead of being limited only to the pressure your air supply can
And they spray very cleanly. I've painted many tens of thousands of
square feet of farm buildings with one I bought for $50 at a welfare
I had a pressure feed paint gun with a 1 gallon tank that we used to
oil-spray the bottom of our vehicles with used airplane engine oil.
Properly adjusted it laid the oil on without too much "fogging".
Putting it on warm helped
Cheap HVLP gun will work for straight filtered oil.
Or filter it, add it to a turkey fryer and toss a few toilet seal rings
(beeswax) in. Then use an undercoat gun and wands to get into all the
spots. The wax will set up and hold the oil in place. Close to the
Bar&Chain oil and wax mix that I and a bunch of others use.
Either way wear a GOOD respirator. Breathing in an oil mist will not
make you healthy !!!!
They are softer than paraffin wax and don't crack as much in cold
weather. I brush melted toilet bowl wax onto the ends of cut logs to
reduce splitting as they dry and shrink.
The MSDS data suggests that Thompson's Water Seal and LPS-3 have had
their active preservatives removed and are now just wax in solvent.
This is second-hand info, but I remember from discussions a decade ago
with some woodworkers...
The old formula was just some volatile solvent and some kind of wax --
not common paraffin, according to reports, but some similar
hydrocarbon wax. The new formula is water-based. It still contains
some volatiles, but it doesn't spread well and it doesn't soak in as
The old formula is still sold in some states. For years, when I wanted
a paint with high VOC, I drove from NJ over to PA and bought it there.
That's how I got my last (current) can of Thompson's Water Seal,
around 5 years ago.
If you're in a state where you can still buy it, the can looks the
same but the original formula says of the VOCs, "600 g/L." The newer
stuff is much less -- something like 1/.3 as much. It's also yellowish
and thicker than the old water-clear formula.
I helped my neighbor paint our dividing fence with the new stuff. It's
OK, but it's a little yucky and tacky.
I've done this before. I used an empty carbon dioxide fire extinguisher. I
soldered a garden sprayer nozzle into the output tube and a Schrader valve
into a hole in the brass neck. Unscrew the whole top, fill to about 2/3 wit
h oil and then reassemble and charge with air to 8 or 10 bar using a compre
ssor. It works well. I might have a picture of it somewhere.
Besides it probably being illegal in Illinoise and salt/water/dust
would likely quickly erase it from the frame, MOST people use a
rubberized undercoating for frames and underbodies, Ig. Why not
recycle the oil and steamclean + undercoat your trucks, for a
Otherwise, what about using an existing aerator spray tip and
adjusting the air pressure to control the overspray? Olive oil can be
sprayed with a hand-pump and regular paint spray can nozzle. Grab a
magnifying glass and look at pressure washer or paint gun tips for
clues into spray containment. It's possible that an HVLP paint
sprayer might work, so you might give that a try, too.
I dislike the oil spray concept from an eco standpoint, and I'm
surprised it isn't illegal. Where's the freakin' EPA now? Watch them
fine a person $50k for leaking a quart of oil onto the ground, but
they let 1,000,000 people leak oil onto the street and flow into lakes
and sewer systems? Go figure!
A little update.
I bought a Harbor Freight "engine cleaning gun" 68290, which siphons
liquid and sprays it with assistance of air.
I hooked it up to a pressurized stainless tank so that oil is pressure
fed into the gun (at a small pressure).
The result seems to be pretty good, a decent amount of oil sprayed
without too much atomization.