What It Means When Your Riding Mower Is Vibrating Excessively And How To Fix It

Riding mowers provide speed and convenience for grass cutting, making them a popular choice among those with larger yards. However, riding lawn mowers can be expensive, especially compared to walk-behind models. Because of the price, you will want to follow steps to ensure your riding lawn mower lasts as long as possible. To protect your investment, do not ignore problems you're experiencing with your riding mower. Failing to maintain the machine could cut its expected lifespan in half. Excessive shaking and vibrating are mower warnings you don't want to ignore. It is important to determine the cause as soon as possible.

Some of the most common reasons for severe vibrations in a riding mower include problems with the blades, a clogged deck, and engine trouble. Maintenance or repair work to fix a vibrating riding mower can be a DIY job, like replacing one or more mower deck blades. However, other problems, such as a bent crankshaft, may be a sign that your lawn mower needs to be fixed by a professional. Here are some tips to help you decide whether you should try to fix a vibrating riding mower yourself.

When the blades under a riding mower's deck are unbalanced or damaged, significant vibration is common. Unbalanced or damaged blades cause an uneven weight distribution as they spin. This is similar to how an unbalanced load in a washing machine can cause vibrations. To balance or replace damaged riding lawn mower blades, you'll usually want to remove the deck. You could also use a mower lift to safely access the underside. Remove the nut or bolt that is securing the blade to the deck. Sharpen or replace the blades if they have nicks or dents before securing them again. If the blade is in good shape, but a blade balancer device shows that it is heavier on one end, you would need to file that end.

A clogged riding mower deck can also lead to excessive shaking. Wet grass clippings cling to the underside of the deck, creating vibrations while the blades spin. If you do not clean the grass out after each use, it can dry in place, causing a matted build-up that leads to shaking. This problem could also explain why your lawn mower keeps dying when it vibrates, as the blades cannot spin normally with the obstruction. To clean the deck, manually scrape dried debris and use a garden hose or power washer to spray away the loosened gunk.

A common cause of vibration in a riding mower relates to the crankshaft, which converts the linear motion the engine produces into rotational motion. If you strike stationary objects with the mower, such as rocks, tree roots, or other debris, you can damage the crankshaft. Replacing a crankshaft in a riding mower is a difficult job that almost always requires a professional. It could cost anywhere from $500 to $1,200. In many mowers, working on the crankshaft requires removing the fuel tank, starting cord, oil pan, and more, which is why most people leave it to the experts. You'd need specialized tools to make this a DIY job, potentially including a torque wrench, seal pullers, seal installers, and a hydraulic press.

Using the wrong fuel, such as diesel in a riding mower designed for regular gasoline, is another fairly common cause of machine shaking. In addition, accidentally putting diesel in the tank can cause smoking, misfiring, and rough idling. Some homeowners can fix this issue themselves, while others will need a professional because you must drain the fuel, remove and clean the carburetor, replace the spark plug, and replace the fuel filter. If you don't feel confident in your ability to complete these tasks, it may be best to seek professional assistance.