Sierra 18-2001 Oil Seal, Replaces OEM 330137

The Sierra 18-2001 is an oil seal designed as a direct replacement component for marine drivetrain applications where OEM part 330137 is specified. Oil seals like this one prevent lubricant loss and block water intrusion at rotating shaft points, protecting gearcase and lower unit components from corrosion and premature wear. Sierra manufactures this seal to match the fit and function of the original equipment part it replaces, making it a straightforward swap when the factory seal has hardened, cracked, or begun leaking.

This is a compact, lightweight component at 0.03 pounds with item dimensions of 5 x 4 x 1 inches, consistent with a single shaft seal rather than a multi-piece kit. It carries UPC 030999309471 and ships as one unit (quantity 1). Because seals of this type are wear items, keeping a genuine-fit replacement like the Sierra 18-2001 on hand simplifies routine maintenance and helps avoid unplanned downtime from a failed seal.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-2001
• OEM Cross Reference: 330137
• Item Type: Oil Seal
• Item Dimensions: 5 x 4 x 1 inches
• Thread Size: NPT 3/4 inch
• Weight: 0.03 pounds
• Vehicle Service Type: Personal Watercraft
• UPC: 030999309471
• Package Quantity: 1

Fitment

Specific make, horsepower, and model-year fitment were not detailed in this listing. Confirm compatibility by matching OEM number 330137 against your engine or lower unit's original seal before ordering.

Replaces (OEM)

• 330137

Frequently Asked Questions

What does the Sierra 18-2001 oil seal replace? The Sierra 18-2001 oil seal is a direct replacement for OEM part number 330137.

How much does this oil seal weigh? The Sierra 18-2001 oil seal weighs 0.03 pounds.

What are the dimensions of the Sierra 18-2001? This oil seal measures 5 x 4 x 1 inches.

Is the Sierra 18-2001 a genuine Sierra part or a generic aftermarket seal? It is manufactured and sold under the Sierra brand as part number 18-2001, built to match the fit of the original 330137 seal it replaces.

How many seals come in the package? The Sierra 18-2001 ships as a single oil seal, quantity 1 per package.

Does the Sierra 18-2001 have a threaded fitting? Yes, the listed thread size for this oil seal is NPT 3/4 inch.

What is the UPC for the Sierra 18-2001 oil seal? The UPC is 030999309471.

Will the Sierra 18-2001 fit my specific engine or model? Exact make, horsepower, and model fitment were not specified for the Sierra 18-2001; the best way to confirm fit is to match OEM number 330137 against the seal currently installed in your application.

What vehicle type is the Sierra 18-2001 intended for? This seal is listed for personal watercraft service applications.

Why would I need to replace an oil seal like the 18-2001? Oil seals harden and crack with age and heat cycling, which can let lubricant escape or allow water to enter the gearcase; replacing a worn seal with the Sierra 18-2001 restores that seal against leaks.

Is the OEM 330137 seal still the correct one to cross-reference? Yes, OEM 330137 is the cross-reference number for the Sierra 18-2001 oil seal.