Parts for Mastercut 21AB45M5059 / 2012: V0b Crankcase Parts

Seals cylinder and piston to prevent combustion gas leaks. Replace if engine uses excess oil, loses power, or has poor compression. Verify fit.

This replacement part is a piston, and it is intended for use in different types of lawn equipment. This is a genuine replacement part made by MTD. This piston is commonly found in lawn mowers and is an important part in the user process. Pistons help transfer the combustion power of the engine to other working parts of the machine. A new piston might be needed if the overall performance of the engine is lacking compared to previous uses. If the lawn mower is not able to build enough power to accelerate, the piston might be faulty. It is also common for the engine to use an excessive amount of oil or put out white or gray exhaust smoke. All of these indicators might mean that the piston should be replaced. This part is a genuine OEM replacement part. This piston is sold individually and can be used in lawn mowers manufactured by MTD.

Connects piston to connecting rod inside the engine cylinder. Replace if pin is stripped, worn, or missing to restore proper piston assembly and movement.

Metal connecting rod assembly that links the crankshaft to the piston in small engines. Replace if rod is bent, cracked, or damaged from wear or impact.

Governor arm shaft for small engines on lawn and garden equipment. Connects governor assembly to carburetor. Replace if worn, damaged, or broken.

Engine won't start or runs rough? This camshaft assembly converts rotational motion to reciprocal motion for proper engine operation. Moderate DIY repair.

Engine won't start after sudden stop? A sheared flywheel key breaks the connection between crankshaft and flywheel. Simple DIY repair.

Engine surging or racing? Replace a worn governor gear and shaft assembly. Critical for speed control on small engines. Moderate DIY repair.

This is a crankcase gasket that seals the crankcase cover to the engine block on a lawn mower. It prevents oil from leaking out of the engine and keeps contaminants from entering the crankcase. Replace this gasket if you notice oil pooling beneath the engine, visible oil seepage around the crankcase cover, or if the gasket is torn or deteriorated.

This replacement part is an oil seal. This is a genuine replacement part made by MTD. This part is used to ensure that oil and other fuel cannot escape from the tank. The seal prevents it from leaking during use to ensure the engine is able to run properly. A new oil seal might be needed if the current one has been damaged. If the seal is worn down and thinner than before, it can cause leaks and oil waste. If this is the case, the seal should be replaced immediately. Oil leakage can cause other issues within the machine. Refer to the owner's manual for more information on how to replace this part. This is a genuine OEM replacement part. This part is sold individually and is sourced directly from the manufacturer.

Replacement oil drain plug for outdoor power equipment engines. Installs in the oil pan to seal the drain opening. Replace if stripped, cracked, or leaking.

Oil drain plug with washer for lawn mowers and outdoor power equipment. Replaces cracked, stripped, or missing drain plugs to prevent leaks.

Oil fill plug assembly for small engines. Seals the oil fill opening to prevent leaks. Replace if cracked, stripped, or missing to maintain proper seal.