Description

The Mercury Quicksilver Gimbal Housing Lock Nut 11-34087 is an OEM-style red Nyloc hex locking nut used in select MerCruiser transom and gimbal housing assemblies. It helps secure the gimbal housing mounting hardware, maintaining clamping force between the outer transom assembly and inner transom plate.

Key Features

• Genuine Mercury/Quicksilver locking nut
• Part number: 11-34087
• Also referenced as 34087
• 1/2″-13 coarse thread
• Red nylon locking insert
• Used on select gimbal housing and transom assembly mounting hardware
• GTIN / UPC: 745061136991

Drive Compatibility

Used on select MerCruiser R, MR, Alpha One Gen 1, and Bravo I / II / III transom assembly applications. Also found across various legacy MerCruiser sterndrive packages, including classic inline and V8 configurations where this nut is shown in the transom assembly diagram.

Serial Number Fitment Notice

Verify fitment by drive/transom serial number, gimbal housing diagram, and original hardware stack-up before ordering. Transom hardware can vary by drive generation, housing style, bolt length, and production range.

When This Part Needs Replacement

Replace this lock nut if the nylon insert is worn, melted, loose, damaged, corroded, or if the nut has been removed during transom or gimbal housing service.

Installation Notes

Install only in the correct gimbal housing mounting locations shown in the Mercury parts diagram. Inspect the mounting bolts, washers, transom plate, seal surfaces, and surrounding hardware before reassembly. Follow Mercury service procedures for torque specifications and tightening sequence.

Alternate/Superseded Part Numbers

Primary Mercury references: 11-34087 and 34087.

Parts Desk Insight

Lock nuts with nylon inserts should not be treated like standard reusable hardware in critical mounting areas. If the insert no longer grips properly, replacing the nut helps maintain transom clamping force and reduces the risk of vibration-related loosening.

Shipping: Ships same or next day for fast Canada wide shipping.