After a winter hiatus, it is not uncommon for mowers to have trouble starting or to make unsettling noises and behave erratically. All are tell tale signs that the mower is not in tip-top shape. Getting Yanked Around. A lawn mower with a starter cord should start in less than 10 pulls. If it takes more to get the engine to fire, then the mower should be serviced. Continuously yanking the cord in order to get the engine to start will not only lead to extreme frustration, but it could also cause the starter cord to break. Sp-sp-sputtering Problems. Sputtering engines indicate that the mower's engine is not receiving the correct blend of air and fuel. This is usually the result of a dirty air filter and carburetor. To help prevent this, regularly brush off the exterior of the machine to keep it clean, and also clean the mower's air filter every three to five uses. Knock, Knock. When an engine makes a knocking noise, it is no laughing matter. This noise can be an indication that the engine needs more oil or is running hot. A knocking engine will lead to reduced power and if unaddressed could lead to the destruction of the engine. The Big Bang Theory. Banging noises coming from under the lawn mower usually indicate a problem with the mower's blade. When the blade hits large rocks, roots or other debris it can become bent or out of balance, causing it to strike the mower's deck. All banging noises should be investigated immediately. Smoke Signals. If the lawnmower is producing puffs of black or blue smoke, it is trying to tell you something. Black smoke is a sign the mower's carburetor is running rich and is burning too much gas. Blue smoke means the mower is burning too much oil. Mowers that are operating properly should not produce any smoke. Going Nowhere Fast. Self-propelled lawn mowers are designed to make mowing the lawn easier, but when the propulsion system is malfunctioning, it can make mowing very difficult. A problem with the mower's self-propel feature is often a sign the transmission is worn or needs an adjustment. Most lawn mower problems are the result of inactivity during the winter or a lack of maintenance. To make the seasonal transition smoother for the mower next year, run it at least once a week during the winter. Allowing it to run for five minutes a week will make a significant difference when starting the mower next spring. Although infrequently operated, rarely cleaned and normally subjected to the harshest of conditions, lawn mowers can last for years if cared for properly. All mowers should be serviced at least once a year, whether they are operated year round or only during the peak mowing season. An annual service will help improve the reliability and efficiency of the mower, and it will also help extend the lawnmower's lifespan. A mechanic that specializes in small engines is best suited to perform maintenance and repairs to lawn mowers. A typical service from a small engine mechanic should include changing the oil, sparkplugs and air filter. It should also include a blade sharpening. A dull blade will tear the lawn's grass rather than cut it, which stresses the lawn and can lead to damaged and diseased grass.