Parts for Craftsman 21AS122R799: Engine Parts

Air filter cleaner for gas trimmers and tillers. Replace when clogged or engine runs rough to restore performance. Confirm fit with your model number.

Seals between carburetor and engine to prevent air leaks and maintain proper compression. Replace if damaged, cracked, or during carburetor rebuild. Verify fit with your model number.

Primer bulb and hose assembly adds fuel to the carburetor for easier starting. Replace if bulb stays hard, won't create suction, or cracks. Verify fit.

Engine won't start or runs rough? This reed valve assembly controls air-fuel mixture in 2-cycle engines. Common fix for power equipment starting issues.

This is an OEM replacement crankcase gasket for use in select MTD lawn and garden equipment engines. The crankcase gasket is responsible for creating a seal between the crankcase and the carburetor mount. This prevents air and fuel from leaking out or getting oil mixed into the carburetor. The gasket is under high pressure at all times and can become brittle or break with age, which will need a replacement. It is important to use genuine OEM parts like this one, which is manufactured to specific standards. It is compatible with machines from MTD, RYOBI, Troy-Bilt, Yard Machines, and Yard-Man. This gasket can be used on select models of blower/vacuums, trimmers, edgers, and tillers. It is sold as an individual unit and does not include any hardware or additional parts. To replace this gasket, the engine will need to be completely cooled and gloves should be worn. The crankcase cover will need to be detached from the carburetor assembly, allowing the old gasket to be removed. The new gasket can be put into place and the cover can be reattached. Then, the entire unit can be reassembled and it will be ready to go.

Replacement fuel cap assembly for tillers and outdoor power equipment. Seals fuel tank, prevents debris entry, and features vent slots. Needed when original cap is cracked, broken, or gasket is worn.

Fuel return line hose routes excess fuel from the carburetor back to the tank. Replace if cracked, brittle, leaking, or damaged to prevent fuel loss.

Fuel line assembly transports gas from tank to carburetor on tillers and outdoor power equipment. Replace if cracked, brittle, or leaking. Verify fit.

Engine won't start when you pull the cord? This recoil starter assembly includes the rope, pulley, and spring needed to restore pull-start function.

Replace a broken recoil spring when your gas trimmer, edger, or blower won't pull-start or the cord won't retract. Simple DIY repair in under 30 minutes.

This replacement part is a rope guide, and it is intended for use in different types of lawn equipment. This is a genuine replacement part made by MTD. This rope guide allows the user to pull start the engine. The rope is connected to the transmission inside the engine that allows it to be turned off and on when desired. A new rope guide might be needed if the current one is damaged or missing. If the user is unable to start the lawn mower, then the rope guide might not be connected and should be replaced. Be sure that the engine is completely powered off while attempting this repair as this part is close to the engine inside the appliance. This part is sold individually and is a genuine OEM part sourced directly from the manufacturer to ensure proper fit in all appliances. Reference the owner's manual for more specific guidance.

Replace a frayed or broken starter rope that prevents your engine from starting. This pull rope wraps around the starter pulley for manual ignition.

This is the clutch drum that houses the clutch that engages the power tools on more than 50 gasoline-powered lawn and landscape devices. The clutch sits inside this housing, which enables it to rotate. When the RPMs of the engine reach a certain point, the clutch expands and causes the drive shaft of the tool to engage. Among the different kinds of equipment that use this clutch housing are cultivators, edgers, and grass trimmers. The clutch, and therefore the clutch drum, receive a great deal of wear for several reasons: the vibration of the engine, the rapid up and down change of engine revolutions, and resistance met by the tools that are transferred back to the clutch and housing. Signs that the clutch is failing include a slow response to increased engine RPMs and an inability for the power tool to engage the drive shaft. In these cases, the clutch and housing should be replaced in order for the equipment to operate properly again. When choosing a clutch housing, it is important to select one that, like this one, is a genuine OEM certified part. This housing is compatible with Craftsman, Troy-Bilt, MTD, Bolens, Yard-Man, and Ryobi equipment.

Few parts fulfill as many roles on lawn mowers and other landscaping power tools than the cover screw. This screw serves to attach metal housing parts, assemblies, and shrouds to one another on equipment such as power vacuums, snow blowers, edgers, tillers, hedge trimmers, lawn tractors, leaf blowers, grass trimmers and cultivators. As these are extremely durable metal screws, they seldom fail under ordinary use. It should be noted, however, that they are most often used at connection and pressure points. Stresses at these junctions sometime loosen screws, causing them to be lost or occasionally resulting in stripped threads. It's also occasionally the case that these screws are lost during repair or routine maintenance of yard equipment because of their small size. Users should make sure to consult their owner's manuals for replacement steps and any special instructions. Because of their small size and the ease of losing them during repair work or maintenance, it's recommended to keep a supply of appropriately sized screws on hand. Most importantly, when replacing a part make sure to use a genuine OEM replacement part. They are manufactured according to the specs of the original parts and are perfect replicas.

Lower clamp assembly for line trimmers and tillers. Secures the lower shaft connection. Replace if loose, cracked, or vibrating. Verify fit with your model number before ordering.

Engine won't start or runs rough? This spark plug ignites the fuel-air mixture in tillers, blowers, and trimmers. Simple DIY fix in under 15 minutes.

This spark arrestor is a genuine MTD part, sold individually. This spark arrestor can be used as a replacement part for the engines of outdoor appliances such as snowblowers, tillers, string trimmers, leaf vacuums, and leaf blowers. The spark arrestor is a safety precaution for such outdoor appliances; it is used to trap and dispel potentially flammable external materials, such as debris and dirt, from the internal combustion engine. A spark arrestor might have to be replaced if it is no longer able to keep flammable materials out of the combustion engine. This could occur as a result of damage to the spark arrestor after it is worn down or has suffered warping or tearing as a result of a direct impact collision or overexposure. If this is the case, the spark arrestor should be replaced with this genuine OEM replacement part. Remember to always wear gloves when handling, repairing, and operating outdoor equipment. This is an OEM part sourced directly from the manufacturer, and it is sold individually. This spark arrestor is compatible with the following brands: MTD, Ryobi, Troy-Bilt, Bolens, Craftsman, Yard Machines, and Yard-Man.

Replacement mounting screw for tillers and outdoor power equipment. Secures components and panels. Order a new screw if original is stripped or missing.

Engine piston ring set prevents fuel leakage and maintains compression. Replace when you notice reduced power, excessive smoke, or oil consumption. Verify fit with your model number before ordering.

Replacement clutch spring for tillers and trimmers. Restores proper clutch tension and engagement. Order a new spring if yours is broken, stretched, or missing.