A lawn mower motor works on precisely the same principal as the one in your automobile — but on a much reduced scale. An oil leak in your mower, like one in your vehicle, might indicate that petroleum is oozing through barriers that should contain it. Sometimes, however, oil stains on the ground come from operator carelessness. In any circumstance, fast diagnosis and therapy save wear and tear on a little engine that runs hot and quick.
Where the Oil Goes
Oil travels from the engine’s crankcase throughout its moving parts, lubricating and controlling friction. Piston, crankshaft and the motor casing that holds them operate smoothly when a thin film of petroleum coats surfaces. When a lot of oil touches alluring surfaces, the result is frequently chugs of white or blue exhaust. Based on Briggs and Stratton, producer of engines for several lawn mower manufacturers, an air-cooled motor may consume around 0.5 liters — approximately half a quart — of motor oil per cylinder — average hand mowers have one — per hour when run at full throttle, the speed at which mowers function when cutting grass. If your mower uses more, you may want to look for a problem because insufficient oil can cause an engine to seize — or worse.
Operator Error
Two common reasons for petroleum leaks haven’t anything to do with mechanical failure, but rather with carelessness from the mower’s operator. After turning a mower for maintenance or cleaning, take care to turn the side together with all the carburetor up. Otherwise, gravity takes over and conducts petroleum all over the side of the motor. Spills may also happen when the mower is shoved over a slope greater than 15 levels. Meanwhile, the crankshaft will churn oil in an over-full compartment to create bubbles, resulting in uneven oil distribution and possible damage. In such cases, the oil typically burns in clouds of smoke. You’ll want to check air and fuel filters in addition to the spark plug for fouling. A pass at the carburetor using a carburetor cleaner spray degreases the room before leaked oil attracts dirt and carries it into the combustion chamber.
Blown Head Gasket
The head gasket, a bit of coated, perforated metal, seals the distance between the engine and cylinder block to extend the vacuum necessary to maintain combustion. Among the signs of a blown head gasket, oil escapes through the breather, occurs when the head gasket corrodes or the liner becomes fragile and fractures. The mower loses compression, stuttering and failing as it runs, eventually refusing to start. A blown head gasket can ruin a cylinder. A simple compression gauge can inform you if this gasket requires replacement.
Other Problems
Other problems are more common in old machines. A worn cylinder may leak oil, especially if seals are old or worn and cracked. An air leak from the crankcase, clogged or inoperative breather, or worn-out dipstick O-ring can all produce oil leaks. Regular maintenance and replacement of worn seals and other parts can treat escapes and prolong mower life.