How to Troubleshoot Snow Blower Shear Pins

Every winter, your snow blower takes on the task of removing several inches, if not several feet of snow, from your driveway and sidewalk. Snow blowers are capable of moving a few tons of snow per hour. The snow blower's augers help you churn through hard-packed snow and ice. However, if the workload is too much for the augers to handle, a shear pin can break. A shear pin is a safety mechanism that is designed to break if the torque on the augers becomes too great. This way the auger's driveshaft won't break if you run over a curb, newspaper or hidden rock.


1. Disconnect the rubber spark plug boot from the spark plug. Refer to your snow blower owner's manual for spark plug location. This will prevent the snow blower from accidentally starting while you troubleshoot the shear pins.


2. Lift the snow blower housing off the ground and support it with a block of wood. Look at the auger's shaft to locate the shear pins. The shear pins connect the auger shaft and the driveshaft. If a shear pin is broken, there could be pieces of it still lodged in the shear pin holes, or the entire shear pin could be missing. Use a hammer and punch to remove shards of the shear pin from the hole.


3. Refer to the owner's manual to find the correct replacement size shear pin. You can find a replacement shear pins at a local hardware store.


4. Take your new shear pins and align them with the shear pin holes. Insert the each shear pin and secure them with the bolt nut, using a socket wrench. Reconnect the spark plug and turn on the snow blower. Engage the augers to ensure the driveshaft and auger shaft rotate.