Sierra 18-9861 Hinge Pin Tool, Replaces Mercury Marine 91-78310, Fits All Mercury Marine Drive Units

The Sierra 18-9861 Hinge Pin Tool is a stainless steel service tool built to remove and install hinge pins on all Mercury Marine drive units. Hinge pins secure the drive unit to the transom assembly, and removing or seating them correctly requires a purpose-built tool rather than improvised methods that can damage the pin or the housing bore. The 18-9861 is designed to do this job cleanly, giving technicians and DIY boat owners a direct way to service the hinge pin connection without guesswork.

Constructed of unfinished stainless steel for corrosion resistance in a marine environment, the tool measures 4 x 1 x 5 inches and weighs 0.13 pounds, making it easy to store in a toolbox or service kit. It is sold as a single tool and finished in white. The 18-9861 cross-references directly to Mercury Marine 91-78310, so it is a straightforward replacement for that OEM tool, and it is intended for use across the full range of Mercury Marine drive units rather than a single model.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-9861
• Product Type: Hinge Pin Tool
• Replaces (OEM): Mercury Marine 91-78310
• Material: Stainless Steel
• Finish: Unfinished
• Color: White
• Dimensions: 4 x 1 x 5 inches
• Weight: 0.13 pounds
• UPC: 808282109691
• Quantity: 1 tool per pack

Fitment

• All Mercury Marine drive units

Replaces (OEM)

• Mercury Marine 91-78310

Frequently Asked Questions

What is the Sierra 18-9861 Hinge Pin Tool used for? It removes and installs hinge pins on all Mercury Marine drive units, giving technicians a direct way to service the transom hinge pin connection without damaging the pin or housing bore.

What OEM part number does the 18-9861 replace? The 18-9861 cross-references to Mercury Marine 91-78310, making it a direct replacement for that original equipment tool.

Which drive units is Sierra 18-9861 compatible with? It is designed to work on all Mercury Marine drive units for removing and installing hinge pins.

What material is the 18-9861 hinge pin tool made from? Stainless steel, left in an unfinished finish, is used for the Sierra 18-9861 to resist corrosion in a marine environment.

What color is the Sierra 18-9861 Hinge Pin Tool? This tool has a white color.

How big is the Sierra 18-9861 Hinge Pin Tool? The tool measures 4 x 1 x 5 inches.

How much does the 18-9861 weigh? 0.13 pounds is the weight of the Sierra 18-9861 Hinge Pin Tool.

Is the Sierra 18-9861 a genuine Sierra part or an aftermarket equivalent? It is a genuine Sierra branded tool, part number 18-9861, manufactured to service Mercury Marine drive units in place of Mercury Marine 91-78310.

What is included when I order the 18-9861? One Sierra 18-9861 Hinge Pin Tool is included per pack.

Does the Sierra 18-9861 have a UPC for ordering reference? Yes, the UPC for the Sierra 18-9861 Hinge Pin Tool is 808282109691.

Is the 18-9861 a specialty tool or a general hand tool? It is a specialty service tool made specifically for removing and installing hinge pins on Mercury Marine drive units, not a general-purpose hand tool.

Is the Sierra 18-9861 covered under warranty? Sierra 18-9861 is covered under Sierra's standard customer satisfaction warranty.