Homesteaders need small engines as a rule. Chainsaws, Lawnmowers, Rototillers, tractors, leaf blowers , weed eaters and a seemingly endless list of other gas powered tools and equipment.
The care and maintenance and occasional repair of these small engines is a skill that is learned over years of toil and trial and error but I can attest to some small knowledge that may save someone else some toil.
There are two types of small engines , two cycle and four cycle and the difference between the two is how they are oiled. Two cycles are oiled from inside the engine the oil being added to the gasoline and four cycles have oil added around the moving parts that needs changed from time to time. Two cycle engines will wear, overheat , and break down if the gas you use is not mixed with the right kind and amount of oil. Most weed eaters and chainsaws take mixed gas- are two cycle engines.
Engines only will run if four conditions are present. There has to be air present, gas present , a spark present at the right time , and exhaust has to have somewhere to go. So your troubleshooting has to involve checking these four conditions.
The easiest part to check is for spark, a spark plug is usually easy to see and easy to remove with a deep well socket. Pulling the start rope with the spark plug out should result it two things- a spark will flash at the end of the plug and the engine should turn fairly easily with air rushing out the hole where the spark plug was. This is the same air and fuel that will blow up in the engine to cause it to run so it is possible for this mixture to ignite with the spark from the loosely hanging plug so care should be taken to dry up any gas and stay clear in case the small amount that comes out of the engine does ignite. If there is no spark there is either a bad plug which is easy to replace and test a new one, a bad plug wire, or a bad coil or magneto. The coil is the piece that sends spark to the plug and the magneto is the part of the mower that is like a generator that produces electricity to charge the coil.One should be familiar with any safety switches and on off switches for your equipment because they are designed to not allow the unit to start unless certain conditions are me. _(Riding mowers wont start unless the blades are disengaged and it is in nuetral, weeeaters and chainsaws often have on off switches -- sometimes which are not immediatley obvious.)
There must be air present, - engines require a different amount of air when they are cold then when they are warmed up. They also need more air when running at high speeds. This is where the breather, carburetor, and choke come in. There are usually screws on the carburetor that can be adjusted to allow more or limit the amount of gasoline to get in. Many times engines that are left with old gasoline or dirty gasoline or water in gasoline require the carburetors to be torn down and cleaned - that's a big job that I wont discuss here. The carburetor is where air and fuel are sent into the engine, it either opens or closes with the throttle. open it allows a lot of gas through. Part of the carburetor is the choke which operated independently of the throttle and adjusts the amount of air that is allowed to the engine, it is usually closed on a cold engine and opens further as the engine is heated up. The breather is the container that usually contains a filter that is either foam or paper that keeps dirt and dust from entering the carburetor with the air and causing wear. The presence of a filter also creates a small amount of resistance that many small engines require to run.
There must be fuel, lines get stopped up, filters get stopped up, old fuel sometimes turns to varnish and builds up in the carburetor, water gets in fuel and the wrong kind of fuel could be used. Small engines do not run without fuel being able to get into the motor. Too much fuel can also be a problem as it will not allow enough air in and therefore will not burn. Also don't forget to to fill your tank with fresh fuel and try to run it all out the last tim e youuse your equipment for the year.
Finally exhaust systems do rust up and get clogged up or rust out and fall apart and many small engines are designed to need the resistance of the specified muffle system to start and run correctly. You can generally tel if a muffler s working correctly by feeling to see if air come out when you turn the motor over with the spark plug in
No comments:
Post a Comment