Sierra 18-9847 Bellows Expander Tool - Replaces Mercury Marine 91-45497A1 for MC-I, R-MR, Alpha One, Bravo One/Two, Blackhawk Drive Units

The Sierra 18-9847 Bellows Expander Tool is a specialty installation tool built to install exhaust bellows on MC-I, R-MR, Alpha One, Bravo One and Two, and Blackhawk drive units. Exhaust bellows are a common wear item on sterndrive boats, and getting a new bellows seated correctly over the gimbal housing and transom assembly requires expanding it evenly without tearing or distorting the rubber. This tool is designed specifically for that job, giving technicians and DIY boat owners a repeatable way to stretch the bellows into place during a drive unit service or bellows replacement.

Constructed from alloy steel for durability under repeated shop use, the 18-9847 measures 15.75 x 5.25 x 3.25 inches and weighs 0.75 pounds, making it easy to store with other drive unit service tools. It is manufactured to meet or exceed the fit and function of the original equipment tool it replaces, so it drops into the same service procedures used for these Mercury MerCruiser drive units. Whether you are replacing a torn exhaust bellows, a shift cable bellows, or servicing the gimbal ring during a routine drive unit teardown, this expander tool is sized for the bellows used on the drive units listed below.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-9847
• Product Type: Bellows Expander Tool
• Material: Alloy Steel
• Item Dimensions (L x W x H): 15.75 x 5.25 x 3.25 inches
• Weight: 0.75 pounds
• Category: Mercruiser Specialty Tools
• UPC: 808282109554
• OEM Cross-Reference: Mercury Marine 91-45497A1

Fitment

Installs exhaust bellows on MC-I, R-MR, Alpha One, Bravo One and Two, and Blackhawk drive units.

Replaces (OEM)

• Mercury Marine 91-45497A1

Frequently Asked Questions

What drive units does the Sierra 18-9847 fit? The Sierra 18-9847 Bellows Expander Tool installs exhaust bellows on MC-I, R-MR, Alpha One, Bravo One and Two, and Blackhawk drive units.

What OEM part number does this tool replace? It replaces Mercury Marine part number 91-45497A1, so it is a direct swap for that original tool in the same bellows installation procedure.

What is the 18-9847 made of? The tool is made of alloy steel, giving it the rigidity needed to expand exhaust bellows without deforming under repeated use.

What are the dimensions of the Bellows Expander Tool? The Sierra 18-9847 measures 15.75 x 5.25 x 3.25 inches.

How much does the 18-9847 weigh? It weighs 0.75 pounds.

Is this a genuine Sierra part or aftermarket? The 18-9847 is a Sierra-branded specialty tool manufactured to meet or exceed the original equipment tool it replaces, Mercury Marine 91-45497A1.

What job does a bellows expander tool actually do? It stretches a new exhaust bellows over the gimbal housing and transom assembly so it seats evenly during drive unit installation, which is exactly what the Sierra 18-9847 is designed for.

Can I use the 18-9847 on an Alpha One drive unit? Yes, the Sierra 18-9847 is listed for use on Alpha One drive units in addition to MC-I, R-MR, Bravo One and Two, and Blackhawk units.

What is included when I order this tool? You receive one Sierra 18-9847 Bellows Expander Tool.

Does this tool work on Bravo Two drive units? Yes, installing exhaust bellows on Bravo Two drive units is one of the applications listed for the Sierra 18-9847.

Is the 18-9847 covered under warranty? Sierra parts, including the 18-9847 Bellows Expander Tool, are covered under Sierra's standard product warranty.