MTD Snowblower Oil Seal 721-0179

Basic information

• Part name: Oil seal
• Manufacturer: MTD
• Category: Snowblower engine and drivetrain seal part
• Primary function: Seals rotating shafts to retain lubricant and keep contaminants out

Technical specifications

• Inner diameter: 0.750 in.
• Outer diameter: 1.00 in.
• Thickness: 0.125 in.

Installation & compatibility

• Compatible models: Fits select MTD, Craftsman, Sears, Troy-Bilt, and Yard-Man snowblower models; confirm compatibility using your models parts diagrams
• Installation difficulty: Medium; requires removing the component the seal fits around to access the sealing surface
• Tools required: Seal puller or flat tool and a driver or socket for installation

Additional information

This oil seal, part number 721-0179, installs around a rotating shaft to keep oil or grease contained while blocking dirt, moisture, and debris. A properly seated seal helps protect internal components and supports smooth, long-term operation.

If you notice oil leakage near a shaft, wet buildup around the seal area, or contamination entering the housing, the oil seal may be worn, hardened, or damaged. Cracking, flattening, or loss of tension can prevent it from sealing correctly.

Before starting the repair, disconnect the spark plug wire to prevent accidental starting. Remove the old seal carefully without damaging the bore, then press the new seal in evenly so it sits flush and seals properly around the shaft.