I am in no way suggesting that I am an expert on small motors, as far as I'm concerned, this is what husbands (and as a last resort, small motor mechanics) are for, however I occasionally find myself home alone and in need of using one of our many small motors. This is intended as a short guide for occasional operators of small motors, such as myself.
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Husband shows off some of our collection of small motors
(note Cheryl, bottom left, would prefer he just threw the ball) |
Small motors come in two types, two-stroke and four-stroke. It is ESSENTIAL that you know which you are dealing with if you need to re-fuel as the most important difference from an operating point of view is that a two-stroke engine needs to have oil mixed with the fuel at a specific ratio, whereas a four-stroke engine takes neat fuel (petrol or diesel) with a separate oil reservoir. If you're interested in the more technical reasons for this (and sometimes that helps me to remember the important details) try this
website. As an example, most of our smaller motors, like the chainsaws, whipper snippers and boat motor are two stroke, whereas the ride-on mower, dam pump and mulcher are four-stroke. A good clue is to look for an oil reservoir, this will indicate that you have a four-stroke motor.
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| The dam pump - we made it a little house to keep out the rain and sun |
Once you've figured out what type of motor you're dealing with, you need to check the fuel level, oil level (if a four stroke) and any other important aspects, such as tyre inflation on a ride-on mower, or the amount of cord left in a whipper sinpper. If needed top up/inflate/refill before use. This is where I can get stuck at times if I don't know exactly how to do what's required. My advice is, if in doubt, stop before you break something!
Next find the appropriate personal protective equipment (PPE). My husband and I both work on an industrial site, so this has become second nature to us. Apart from being able to bring home various items from work, we also feel wrong doing work without it. The minimum is usually long pants, long sleeves, steel-capped boots, safety glasses, hearing protection, sun protection and gloves. For the whipper snipper we also sometimes use goggles and/or a visor depending on the work. I see lots of people whipper snipping in thongs/jandles and shorts, I can't believe it, I would not feel comfortable doing that, I recommend you invest in some decent PPE and look after it, it may save your fingers, toes, eyesight or your life one day.
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| Appropriate PPE is essential for safe work |
After you've checked everything and suited up, you're ready to start the engine. Most engines start best with the choke on (unless they have just been running, say after refueling) as this restricts air access to the engine and with a fuel-rich mixture it can get started more easily. If its not an electric start, you have to pull the cord to get the motor turning over until it can sustain itself. Some two-strokes will also need you to pump in a little fuel to get it started, not too much though! Best to press the fuel bulb only once or twice and put some more in later if that's not enough, otherwise you will flood it and have to wait for the fuel to drain back out. Generally you also hold the throttle on a little bit for a two-stroke as you start it as well (our whipper snipper and chainsaws have a clip to hold down the throttle the right amount, otherwise you'll have to do this manually). Now you pull the cord a few times until the motor turns over, then open the choke and pull the cord again until the motor starts. You may need to repeat this a number of times if its a fiddly one, our large whipper snipper usually needs to be thrown to the ground and sworn at before it will start. Chez also finds it helps to bark encouragement at this stage.
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An excited Kelpie is just what you need if the motor won't start
(she likes chasing push bikes too) |
Once the motor is running you can adjust the throttle and off you go, it shouldn't give you any trouble until it runs out of fuel.
Any tips for working with small motors?
Two strokes can be the most annoying things. I had fun with the small generator I use for power tools last time I went to the property.
ReplyDeleteBecause it only gets used occasionally sometimes the oil left in it separates from the fuel again and when you go to use it, it smokes and clogs the carby.
I had that damn carby off cleaning out all the tiny orifices so many times until I finally found the right needle and seat that had been blocked.
Stihl advises to drain the fuel if you will be storing for a while. But the one hung lo genny has no easy way to drain the tank so I usually just leave it and deal with it when I have to.
Another thing I have learnt is don't sit engines where they can suck up dirt.Even if you have a good air filter there's a lot of other parts moving or otherwise that can be affected. Put a sheet of fibro or timber under them rather than sit them in the dirt.
The mechanical engineer in me wants me to point out that the correct term for a device that converts chemical energy to kinetic energy is an engine rather than a motor. A motor is a device that converts electric energy to kinetic energy. I'm not sure how a pneumatic motor fits in as they only really are more of a turbine turning air movement into rotational or linear kinetic energy. I digress. Otherwise thanks for the helpful tips Liz!
ReplyDeleteFrom Burton