Sunday, October 17, 2010

The Tao of Internal Combustion Engines

I really would like to post my current projects. Unfortunately they are Christmas presents, and the recipients read this blog. Sigh. Well, I have a number of posts up my sleeve, as it were. One of them concerns the Ubiquitous Infernal Combustion Engine or UICE for short. We are all faced with these things, unless we live in apartments. At Chalupy, we boast (or deplore) a lawnmower, three tillers in various stages of disrepair, a snowblower, four chainsaws, two used frequently, and an edger or string trimmer. This does not count Vicky, my car, or Lysander the tractor. Every one of them worked fine when new. The problem is to keep them that way. So here are short and bitterly learned lessons on keeping these UICEs going.

First, a bit of Taxonomy, or classification if you prefer a more common word. All UICEs fall into two big classes:
  1. Two-cycle engines. Here the gasoline is mixed in with the oil.
  2. Four-cycle engines. Oil is in one place, fuel in another.
Examples of two-cycle or two-stroke angines are chainsaws and trimmers. For four-cycle engines anything else goes, e.g. cars, most tillers, and lawnmowers. The Tao is a little different for each type.

There are likewise two big cycles in the Tao of UICEs:
  1. The fall cycle: putting away the stuff that is no good in winter (e.g. lawnmower).
  2. The spring cycle: prepping the stuff you will use in summer, again e.g. lawnmower.
In this post I will concentrate on the fall cycle. Let's put stuff away for winter here. There is a simple Golden Rule that will keep your contraption running much longer than other people's: drain the gas out of the engine. Not too complicated a rule, eh? But how do you do it? If you are clever and know your, say, lawnmower, you will contrive to mow the last blade of grass just as the mower coughs and runs out of gasoline. If not, you will have to siphon the gas out of the machine. Fortunately, auto parts stores sell siphon pumps for just this purpose. Plastic contraptions with a squeeze-bulb that allows you to suck (most of) the gas out. Then start the blasted thing and let it run dry. If you do not do this, your gas will turn to jelly over the winter and the machine will not start in the spring.

The second sound rule is to stabilize your gas. This is indispensable for anyone who lives in a cold climate. Gasoline has a very limited lifetime, about three months from the time you buy it. So you add some obscure chemical to it, and it lasts a year. Essential for snowblowers, and really, really good for everything else. I buy some stuff called Sta-bil, because I can get it at the Willow hardware store. Stabilizers are said to keep gas from turning to jelly. Maybe so. I prefer to run my machine dry anyway. You add it according to directions on the container. I buy gas in 5-gallon lots (20 liters). I put the proper amount of Sta-bil into the 5 gallon container before I fill it up, and let the trip home shake it well.

If you have a two-cycle engine (e.g. edger or chainsaw), get rid of the gas before storing and that's it. My chainsaws live indoors in winter and always use stabilized gas.

And a special word about snowblowers. These UICEs are unusual because they have to run in the winter. So the cycles are completely reversed. You drain the gas in spring and in the fall you do the spring thing. What's the spring thing? I'll get to that next spring, I hope. If anyone really wants to know, right this instant, do the unusual: drop a comment! I will do a quick rundown for you.


  1. I just wanted to leave a comment. My UIC (a 2002 Ford Focus) sat in storage for three years, with apparently some gas left in it. It started on the old gas, oddly. Why is this, in view of the whole 'gasoline-three-month-shelf-life-principle?'

    Johnny Vagabond

  2. enjoyed reading your blog. I run the old mower till its out of gas every year. I also enjoyed reading about the hacksaw knife.

  3. To Johnnt Vagabond: a car is much more tolerant of bad gas than a one-cylinder engine. The older the car, the more tolerant it is. A car from the 1940s will run on 80-octane gasoline (if the carburetor has not accumulated gunk). The fuel tubing is wider, doesn't clog as much. Modern cars have injectors. So the last bit of gas gets spritzed into the engine and does not clog the carburetor. In fact there is no carburetor to clog! However, the colder the winter the more it will hurt you. In Alaska, of course we hit -30C routinely.

  4. Oh, I forgot. A very good way to dispose of your extra gas (but NOT if it's two-cycle) is to put it in the car. Especially if there is plenty of gas in your car. The car, as said before, will tolerate some bad gas. If it's from a two-cycle engine, you just have to dump it.