Fuel Ratting Lao Tze Style

Currently, I have half a tank of fuel; that’s enough to get me through this cold snap without the pipes blowing up. The last few days have been an interesting, exciting, scattershot mess.

One thing I learned is that oil appears to have less mass than water; getting highly chilled diesel fuel on your hands is not anywhere near as bad as getting highly chilled water. I theorize that thermal mass tracks actual mass but I’m not going to examine that further. Another thing I learned is that electricians’ tape stickum dissolves into what amounts to black dye if you get diesel fuel on it. If you ever need to get electricians tape stickum off something, there’s no need to reach for a nastier solvent; diesel oil will do.

I got a truckload of diesel fuel:

Then I needed to figure out how to get it into the tank. The tank’s inlet is under my porch where it’s easy to knock your brain out on a beam:

The filler and vent pipe are the things sticking out of the cinderblock wall. I am going to do everything I can to keep the propane from getting involved in this situation. Diesel oil is relatively mellow stuff compared to propane.

The broader context is this: my propane is outdoors on the other side of the cinderblock, the oil tank is right on the other side of that wall from it. It’s cramped and a bit dank under there; my dogs used to hang out in the cool during the summer.

The mower can’t move because I let the tires flatten in the winter. Actually, they do it on their own.

This is Plan A:

I’m aware that the drill will be full of sparks and I need to be careful not to have oil fumes coming off of me when I engage it. The little rotary pump says on it “not for use with flammables” but I assume that it was put there by a lawyer. Or, that something inside of it will dissolve to goo. The pump is $9 and it seems worth a try. The hose is unnecessarily long because I want to be out from under the porch, in the wind, so fumes can’t build up. That means I’ll freeze but freezing (I’ve done it before) is better than burning (that would be a new once-in-a-lifetime experience!).

It didn’t work. First thing I realized is that I can’t see a damn thing through the hose, so I have no idea what’s happening. I actually have a flow-meter I could have patched in there, but it’s 10 miles away at the shop. So, I run the thing for a while and disconnect one side – fuel squirts out. Then I hook it back up and run it more – the tank does not get discernably lighter. I will freeze before I can transfer 5 5gal tanks. What’s Plan B?

I went inside and made huffing noises and drank tea for a while, then got a big spade-bit and solved the problem Lao Tze-style:

With gravity on your side, things work better.

Lao Tze did not say that, but it works. I took the loop up some once I fed the line farther down the fuel inlet. Drilling a hole in the porch was bothersome but I did it where I doubt anyone will ever notice it – and, besides, you never know when I may need it again.

Up top, there’s a funnel, which I sealed with electrician’s tape and wired to a convenient porch-table.

My hypothesis turns out correctly – once the fuel fills the hose completely, it falls down (thank you, gravity!) and sucks itself rapidly down the hose. I can pretty much pour it down as fast as I can and it just sucks it right in. It’s also convenient to have a table and a chair.

Water in the fuel is bad,and I worried about that, a little.The zip-loc bags with the little zipper are useful for terminating things that need to stay dry, as long as you can orient them the right way. No snow is going to fall into my tank! Doing that gave me time to think about things, including fuel line dryer and gravity-feed pumping systems. It seemed like forever that I was pouring oil but it was probably only a few days.

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I will digress into some experiments I did with fuel line drying and gravity-feed pumps when my fingers are working better. I also had some thoughts about jerrican safety systems that I will post, if I am in a particularly grumpy mood.

Gloves are great for protecting your hands against cold but using a razor-sharp kiridashi to cut hose when you can’t feel your hands can result in after-bleeds.

There’s a light in every diesel truck, and it says “water in the fuel.”
If it comes on, well, then you’ve got water in the fuel.
Run it too long, and your truck just dies.
Run it too long, and your heart just gets broken… – Fred Eaglesmith


  1. Owlmirror says

    So how does fuel usually get in there? Does the fuel truck driver have to crawl around and duck down to connect the hose?

  2. says

    So how does fuel usually get in there? Does the fuel truck driver have to crawl around and duck down to connect the hose?

    Yup! They have a very long hose and an auto-retraction mechanism. It’s pretty easy to get in there if you are careful not to knock your brain out on a beam. I asked them about whether I could put an extension on the filler so that it’d be easier to reach but apparently I’d need to get a real engineer to come out and inspect it.

    From the speed with which the fuel truck refuels I can only conclude that it’s pumping hella lots of fuel at a pretty good pressure.

  3. kestrel says

    Wow – I had been under the impression you needed a space ship for that, but apparently Fuel Rats are resourceful and get the job done no matter what the difficulties are! Also I’m impressed with how much you had to haul. 125 gallons – yikes.

    I’ll keep that in mind about electrician’s tape. We do have to haul diesel fuel about once a month but the amounts are not near to what you just did, and the delivery system is far easier and accessible.

  4. says

    UPDATE: The oil company called and they were very worried because they hadn’t heard anything from me. Apparently they have a dozen customers in similar situation and they’re kitting out a 4×4 with a 150gal tank to do deliveries for people with awful driveways. That’s very good of them; I told them I have it sorted for the meantime and if they have an old person with a dog who needs fuel, refuel them first.

  5. komarov says

    Re #6:

    That is good of them and I feel mildly bad for immediately wondering what would be worse PR for them: The old person and their dog freezing because they ran out of fuel or the DIY guy blowing up his farm trying to solve the problem on his own.

  6. travisd says

    You will be hard pressed to ignite diesel with a measly spark from a tool. Even more so when cold. The canonical demo of this is someone putting out a lit cigarette in a puddle of diesel. This is part of the reason why diesel fueling aparatus is usually messier than gasoline – diesel doesn’t readily vaporize and normal ambient temps, so it stays there and collects dirt.

  7. travisd says

    Also – buying in that quantity, hopefully you found a place selling off-road diesel, so you weren’t paying road taxes on it unnecessarily.

  8. johnson catman says

    If you ever need to get electricians tape stickum off something, there’s no need to reach for a nastier solvent; diesel oil will do.

    WD40 works just as well, and it doesn’t stink nearly as much as fuel oil. And it is easier to clean off the residue.

    I used to work as a fuel oil delivery driver. Our trucks had a 125-foot 2″ hose, so they could pump between 60-100 gallons per minute depending on if you let the truck low-idle or ran up the RPMs. I worked many days where the temps were really low, and when it was like that, we added kerosene into the fuel oil to keep it from gelling. With your tank inside, you wouldn’t necessarily need to worry about that though. Fuel oil as a heat source pretty much got replaced by natural gas (where available) or propane (in the country) here (NC).

  9. cvoinescu says

    The main difference between water and diesel oil on your hands is not specific heat capacity. Water does indeed have a high specific heat capacity (looking at a table of common materials, only liquid ammonia and gaseous hydrogen are higher), but there’s too little liquid on your hands for its heat capacity to make a lot of difference. It’s the very high latent heat of evaporation of water, and, more importantly, the fact that it vaporizes at a much, much higher rate than diesel oil. In fact, if you get diesel oil (or any oil) directly on your hands, they feel warmer than when dry, because the oil blocks the evaporation of water from your skin, and thus reduces cooling. When wearing gloves, oil or no oil should make practically no difference.

    About the tape adhesive: for all their claims about orange peel oil and stuff, the main ingredient of Goo Gone is kerosene (or a similar petroleum distillate, somewhat lighter and more refined than heating oil). It works very well. WD40 also works, and smells better than diesel oil.

  10. coragyps says

    Like travisd said – the flash point of diesel is typically 130F or higher, so it’s damn tough to get it to burn if the bulk fluid is at -20F. Gasoline is a very different story – it can have a flash point below 0F.

  11. sonofrojblake says

    Re: removing goo – ANY organic solvent will do. Depending on the amount you have to deal with, acetone (nail polish remover) might be the best option as it’s clear, relatively pleasant smelling, and very very volatile. Pour it on, let it dissolve the goo, wipe it up so that all the goo is on your rag, wait a minute… and your rag is dry.

    I hadn’t realised that the latest E:D update included fuel limpets for SRVs… (have you seen orrery mode?). Also the new scanner makes finding the Voyager probes easy.

  12. Bruce says

    Compared with hydrocarbon fuels, water’s higher density, higher heat capacity, and higher heat enthalpy of vaporization (or evaporation) are all due mostly to the fact that H2O is a small molecule that does a LOT of “hydrogen bonding”, which hydrocarbons can’t do. So the chemistry and physics observations made on this post so far are all scientifically justified. Cool stuff.

  13. rq says

    This is nice to hear, though you’ve set it out in such a calm, methodical manner.
    Meanwhile, in the background, I hear a lot of swearing and random running around in a vaguely directional panic. Your comfortably atmospheric photos overlay an energetic set of vigorous actions and probably a small emotional roller-coaster or two. Unless you’re a far less dramatic person than I am. :D
    (Sometimes things happen with our heating system, and it’s a rapid-fire of figuring out what needs to be done, what can be done, what is the worst that could happen, doing something, some waiting and seeing, adjusting for short-term sustainability (because in the long-term it gets fixed or we forget about it). All on a very specific time-limit (e.g. “I need hot water by 6AM tomorrow morning. Solve for x, STAT!”).

  14. says

    Diesel fuel is indeed less dense than water (not really surprising: back in the days before milk was all homogenised and semi-skimmed, the cream used to float to the top if left to stand long enough), but that’s not the main reason why it does not feel as cold as water.

    Diesel fuel has a specific heat capacity of about 1800. That means it takes 1800 Joules of energy to make 1kg. of the stuff 1 degree hotter. Water has a specific heat capacity of about 4200. That means it takes about 4200J of energy to make 1kg. of water 1 degree hotter. (This is also the definition of a food calorie.)

    Just ten grams of diesel at 0° hitting your body and being heated to 37° will suck 1800 * 0.01 * 37 = 666J out of you …..

  15. lorn says

    Flash point of diesel, the point where sufficient flammable vapors are emitted from pooled liquid to allow an intimate mixture with air necessary for combustion (yes, I knew it was high but looked it up) is listed at 126 to 205 F (52- 96C). Ignition temp is 210C.

  16. voyager says

    What a clever solution and I like the added table and chair. They’re a nice touch that makes it all seem so very, very civilized instead of the cold, heavy, dirty grunt work that it was.

  17. cvoinescu says

    Just ten grams of diesel at 0° hitting your body and being heated to 37° will suck 1800 * 0.01 * 37 = 666J out of you …..

    That’s a bit pessimistic. It’d take a lot of time for anything you touch with your hand to get to 37°C. Your hands are usually not that warm to begin with, and the body is pretty stingy at replenishing heat lost in the extremities. This is actually an evolved trait in some animals: they have pretty effective counter-current heat exchange between arterial and venous circulation in the limbs. They keep their limbs cold to conserve body heat. Humans have only a vestige of that, but with vasoconstriction and such, your skin will get pretty cold, so that diesel will not reach anywhere near body core temperature.

    Plus, your body makes some 100 J of heat every second just sitting there — much more if you’re out in the cold doing something physically demanding, so even 600 J does not sound like a lot.

    For comparison, one gram of water evaporating sucks about 2300 J (the exact value depends slightly on temperature).

    A experiment: if you compare putting your hand in a bucket of cold water to putting it in a bucket of cold diesel oil, not only is the water slightly denser and has a much higher specific heat capacity, it’s also much less viscous, so convection will move heat away from your hand much more quickly. Fuel oil would barely move, and it’s a poor heat conductor too. Basically, your hand would heat a thin layer of oil around it, and that would only slowly conduct heat away into the bulk of the liquid. My guess is that the diesel would suck at most a tenth of the heat that water would.

  18. Knabb says

    There’s a lot of equilibrium energy conversion going on here, and that’s a secondary concern at most. This is a heat flow problem, which means we want to be looking at thermal conductivity*, for the rates in which this happens. Note that water is about 4.7 times as thermally conductive here, which heats/cools stuff a lot faster.


  19. says

    @ cvoinescu, #19: I agree, it was a bit contrived. But when I saw that 18 and that 37, it was irresistible!

    @Knabb, #20: The n+1th Law of Thermodynamics: For every “simple” energy calculation, there will be another scientist along to invalidate one of the simplifying assumptions.

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