Why does my lawnmower vibrate?

Answer by  GilFinn (2065)

Most likely cause is an out-of-balance blade, usually caused by damage such as hitting a rock, or large piece of wood. Most blades can be rebalaced with simple sharpening tools such as a good file.

Answer by  fred19 (73)

A motor mount bolt could be broken. You may have hit something when you where mowing and bent the crankshaft and its off balance.

Answer by  Srfingfreak (697)

The most likely source of this problem is in a chipped or broken blade. The blade could also just be coated in chopped grass on one side, unbalancing the blade. Turn your mower off and lean it back so you can inspect the blade for any problems.

Answer by  LeheckaG (1826)

A bent, damaged, dull, loose, or unbalanced cutting blade is the most common cause of lawnmower vibrations. Other possible causes include: low engine oil, loose engine mounting bolts, self-propel drive mechanism wear, engine parts worn out, engine misfires (bad gasoline, bad or fouled spark plug, clogged dirty air filter), bad muffler, ...

Answer by  Amber40 (24961)

More than likely this is caused by the blade being off-balance. Try removing it and cleaning it. If it still vibrates you should have a professional take a look.

Answer by  Marybeth (841)

You have to maintain a lawn mower, you need to due tune ups, change the oil, if you store the mower for any length of time, you need to drain the gas and put in fresh gasoline. You might need a new spark plug.