How Do I Fix a Craftsman 917375520 Mower?

Check to ensure there is an adequate fuel level in your Craftsman mower's gas tank. If you suspect the gas has been left in the tank over the course of the season, you will need to run the mower idly until all the old fuel burns away.

Refill the Craftsman 917375520 mower with fresh fuel once all the old fuel has burned away.

Turn off the Craftsman mower and check the engine if fuel was not the issue. Find the spark plug on the right side of the engine assembly if the mower is having problems starting. A thin, black ignition wire should connect to the rear of the plug. If it does not, reinsert it into the rear of the plug.

Check the spark plug for any brown or white corrosion on its end. Also, ensure the white band around the end of the plug is not "blistered" and featuring black specks. If any of these conditions are present, disconnect the ignition wire from the back of the plug and connect it into the rear of a replacement spark plug.

Check the Craftsman mower's carburetor if the mower will start but "sputters" and runs hard, whining as the engine runs. The carburetor may also be the issue if the mower starts initially but the engine fails shortly thereafter. Find the distinctive bowl-shaped Briggs & Stratton carburetor along the right side of the engine assembly.

Turn on the Craftsman mower and allow it to run as you adjust the carburetor.

Find the air adjustment needle valve on the underside of the Craftsman's carburetor bowl. Turn this valve all the way to the right.

Turn the needle valve one turn back to the left, listening to the Craftsman mower as it runs. Sputtering may lessen or cease entirely. If so, leave the needle valve adjusted to this point.

Continue gradually turning the Craftsman mower carburetor's needle valve back to the left, checking after each adjustment for an improvement of the engine's running state. Make adjustments until the engine runs smoothly and ceases to sputter or whine.