Sierra Prop Nut 18-3703, Replaces 11-88228, Fits 9.9-25 HP Outboard Motors 1986-Up

The Sierra 18-3703 Prop Nut is a machined aluminum propeller nut built to secure the propeller onto the prop shaft on 9.9-25 HP outboard motors, 1986 and up. It is manufactured to meet or exceed the quality of the original equipment part it replaces, giving boat owners a dependable, exact-fit hardware option when servicing the lower unit or swapping a propeller.

The nut uses a 3/8 inch - 16 UNC thread with a Class 2B thread fit and a fully threaded, flat-style design, finished in a machined silver appearance. Its compact, lightweight construction (0.02 pounds) makes it an easy, low-cost keep-on-hand spare for anyone who regularly removes or reinstalls a propeller.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-3703
• Product Type: Prop Nut
• Material: Aluminum
• Thread Size: 3/8 inch - 16 UNC
• Thread Type: Unified National Coarse
• Thread Class: Class 2B
• Thread Coverage: Fully Threaded
• Screw Head Style: Flat
• Compatible Groove Diameter: 0.38 inches
• Finish: Machined
• Color: Silver
• Weight: 0.02 pounds
• Number of Pieces: 1
• UPC: 808282111953

Fitment

• 9.9-25 HP outboard motors, 1986-Up

Replaces (OEM)

• 11-88228

Frequently Asked Questions

What does the Sierra 18-3703 prop nut fit? The Sierra 18-3703 prop nut fits 9.9-25 HP outboard motors, 1986 and up.

Is the Sierra 18-3703 a direct replacement for OEM part 11-88228? Yes, the 18-3703 replaces OEM part number 11-88228 and is manufactured to meet or exceed the original equipment part's quality.

What material is the 18-3703 prop nut made from? It is made from aluminum with a machined silver finish.

What thread size does the 18-3703 use? The 18-3703 prop nut has a 3/8 inch - 16 UNC thread with a Class 2B thread fit and is fully threaded.

How much does the 18-3703 prop nut weigh? The Sierra 18-3703 prop nut weighs 0.02 pounds.

Is this a genuine Sierra part or an aftermarket copy? The 18-3703 is a genuine Sierra-manufactured prop nut, built to meet or exceed the original equipment part it replaces.

What comes in the box when I order the 18-3703? You receive one Sierra 18-3703 prop nut; no additional hardware or cotter pins are included.

How does the 18-3703 differ from the Sierra 18-3704 prop nut? The 18-3703 replaces OEM number 11-88228 for 9.9-25 HP outboards 1986-Up, while the 18-3704 is a separate part number that replaces a different OEM number, 11-69578, so the two are not interchangeable.

What is the compatible groove diameter on the 18-3703 prop nut? The Sierra 18-3703 prop nut has a compatible groove diameter of 0.38 inches.

What is the UPC for the Sierra 18-3703 prop nut? The UPC for the Sierra 18-3703 prop nut is 808282111953.