Sierra 18-2768 Transom Seal, Replaces OMC 909527, Fits 1978-86 OMC Sterndrive All

The Sierra 18-2768 Transom Seal is the gasket/seal assembly that mounts at the transom of an OMC sterndrive, sealing the connection point between the boat's transom assembly and the outdrive unit to keep water out of the bilge and engine compartment while allowing the drive shafts and cables to pass through. This is a 22-hole seal built to the OEM bolt pattern for a direct, gasket-tight fit at reassembly. Sierra manufactures the part to meet or exceed the specifications of the original equipment it replaces, making it a straightforward like-for-like replacement when servicing a worn, cracked, or leaking transom seal during a sterndrive rebuild or bellows/seal replacement job.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-2768
• Category: OMC Bellows & Transom Seal
• Bolt Hole Count: 22 hole
• Weight: 2.42 pounds
• Dimensions: 0.39 x 0.39 x 0.39 inches
• Exterior Finish: Machined
• UPC: 030999562944
• OEM Cross Reference: 909527

Fitment

• OMC Sterndrive, 1978-86, All

Replaces (OEM)

• 909527

Frequently Asked Questions

What boats does the Sierra 18-2768 transom seal fit? The Sierra 18-2768 fits OMC Sterndrive applications for 1978-86, all models.

What OEM part number does 18-2768 replace? It replaces OEM part number 909527.

How many bolt holes does this transom seal have? The 18-2768 is a 22-hole transom seal, matching the OEM bolt pattern for 1978-86 OMC Sterndrive units.

How much does the 18-2768 transom seal weigh? It weighs 2.42 pounds.

Is the Sierra 18-2768 a genuine OEM part or an aftermarket replacement? It is a Sierra-manufactured replacement part engineered to meet or exceed the specifications of the original OMC 909527 transom seal it replaces.

What are the dimensions of the 18-2768 transom seal? The Sierra 18-2768 measures 0.39 x 0.39 x 0.39 inches.

When would I need to replace the transom seal on my OMC sterndrive? The transom seal should be replaced when it is cracked, worn, or leaking, which is typically checked during a sterndrive bellows and seal service to prevent water intrusion at the transom.

What is the exterior finish of the 18-2768? The Sierra 18-2768 transom seal has a machined exterior finish.

Does the Sierra 18-2768 come with a warranty? Yes, the 18-2768 is covered under Sierra's standard customer satisfaction warranty like all Sierra parts.

Will the 18-2768 fit an earlier OMC sterndrive from the late 1960s or early 1970s? No. The 18-2768 is designed for 1978-86 OMC Sterndrive applications; earlier OMC sterndrives use a different transom seal.