121-778R7089221 (1991) MTD Lawn Mower - Overview

This carriage bolt measures 5/16-18 x .75 and fastens two parts in your machine together. It has a round domed head and a square underside so the bolt does not rotate once it has been secured into place. If it has signs of deformation or wear, you will need to replace it. To unthread this bolt, you need an adjustable wrench to loosen the ...Read morenut found on the end of the bolt. You may need to apply a lubricating oil to the bolt if it is stuck. You may need to clamp down on the head of the bolt with pliers while continuing to turn the nut counterclockwise. You can then slide the carriage bolt out of its hole or tap it gently with a hammer. This bolt is a standalone product and the nut is not included. This bolt was sourced directly from its manufacturer.

The hex bolt attaches to the washer and the square key. This part is an OEM from Craftsman for use in snowblowers and lawn mowers. It is available as an individual replacement part and is made of metal. If this item becomes broken or stripped it will need to be replaced and may require a socket set during the installation.

This Star Knob, which may also be simply referred to as a Knob, is sourced directly from the manufacturer for use in lawn mowers and snow blowers. This part provides a quick-release for handles to fold down, and connect upper and lower handles. It is made of metal, is black, is not part of a kit or assembly, and is sold individually. Th...Read moreis part will need to be replaced if it has become cracked, worn, or damaged. The most common cause for this part needing to be replaced is worn or stripped threads no longer being able to grip. You will need a wrench or socket set and a torque wrench to complete this repair. It should be torqued to the manufacturer's recommendation. Customers rate this repair as Easy.

This is a genuine replacement part manufactured for use with outdoor power equipment. The screw includes a lock washer and is commonly used to secure the motor to the frame. This screw has various applications based on the model of the machine it is used with. The screw is sold as an individual replacement part, please see model diagram for part location and usage.

This is an original Craftsman replacement part. The carriage screw is designed by the manufacturer for use in snowblowers and lawn tractors. This part is made of metal, and may be found in various locations in the machine, depending on model. Please be aware that there are different screws used in the machine. Refer to the parts diagr...Read moream to be sure of ordering the correct part. You will require a wrench when replacing this item. This part is sold individually.

This is an authentic replacement part that has been sourced from the original manufacturer to be used with trimmers and lawnmowers from Ryobi and MTD. The metal nut is used with different types of machines and the application of the nut can vary based on the model of the equipment. It is recommended to verify the parts compatibility and u...Read moresage by reviewing your models diagram. This nut is available as an individual replacement part. A hex socket wrench and a driver are needed when installing this part.