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FLASHSALE26

Transom Seal Boot 22-Hole – Fits OMC Stringer 1978–1986 (Replaces OMC 909527)

Regular price $89.99

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Orders are typically processed within 1–2 business days.


U.S. orders usually arrive within 6–15 days, depending on stock location and destination.


International delivery times may vary due to customs processing.


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If you have any questions, feel free to email us at info@sierramarines.com, and we’ll get back to you within 20–36 hours.

Product Details

This Transom Seal Boot 22-Hole is engineered for OMC Stringer Sterndrive units manufactured between 1978 and 1986. It installs on the transom plate to create a durable, watertight seal, preventing water intrusion where the sterndrive assembly connects to the hull.

This component is a direct replacement for multiple OEM and aftermarket part numbers, including OMC 909527, Sierra 18-2768, and Mallory 9-72812.

  • Secures to the transom plate via a 22-bolt hole pattern.
  • Made from durable rubber designed to withstand the marine environment.
  • Package includes one transom seal boot.

Part Number Matrix

Use this matrix to confirm equivalent references across OEM and aftermarket.

Brand Part Number
OMC 909527
OMC 0909527
Sierra 18-2768
Mallory 9-72812
GLM 86710
EMP 26-08671
BJKIEW 106
MTC 50038

Engine & Model Compatibility

Confirm your engine model/year in the table below.

Brand Model Years OEM Part No. Notes
OMC Stringer Sterndrive 1978–1986 909527 / 0909527 22-hole version

Technical Specs

Product Type
Transom Seal Boot
Application
OMC Stringer Sterndrive units 1978–1986
Configuration
22 bolt holes
Installation
Bolted to transom plate, 22 bolt holes
Material
Rubber
Color
Black
Warranty
90 days (Jetunit brand)

What’s in the Box

  • 1 x Transom Seal Boot (Replaces OMC 909527)

Installation Notes

  1. Disconnect the battery and follow all safety precautions before starting work.
  2. Access the transom assembly, which may require removing the sterndrive unit according to the manufacturer's service manual.
  3. Carefully unbolt and remove the old transom seal boot, noting the orientation of the 22 bolts.
  4. Clean the mounting surfaces on the transom plate thoroughly, removing all old sealant and debris.
  5. Apply a marine-grade sealant recommended for this application to the mounting surface or the new boot.
  6. Position the new 22-hole seal boot, ensuring all bolt holes align perfectly.
  7. Install and tighten the bolts in a crisscross pattern to the torque specified in your service manual to ensure an even seal.
  8. Reassemble the sterndrive components and reconnect the battery.
  9. After launching, check for any signs of water leaks around the transom seal.

Troubleshooting & FAQ

How do I confirm this boot fits my OMC Stringer drive?

This boot is specifically for the 22-hole transom plate found on OMC Stringer Sterndrive models from 1978–1986. Please verify the year of your drive and count the bolt holes on your existing transom plate before ordering. This part will not fit earlier models or those with a different bolt pattern.

What are the signs my old transom seal is failing?

Common symptoms of a failed transom seal include water leaking into the bilge area, especially when the boat is in the water, and visible cracks, perishing, or hardening of the rubber boot material. A compromised seal can lead to significant water damage and should be replaced immediately.

How often should a transom seal boot be replaced?

Transom seals are a critical wear item. While there is no fixed replacement interval, they should be inspected annually for signs of cracking, stiffness, or deterioration. Proactive replacement every 5-7 years is often recommended as preventative maintenance, even if no leaks are present.

Is this boot different from other OMC versions?

Yes. This is the 22-hole version for 1978–1986 OMC Stringer drives. Other models, particularly earlier ones, may use a different bolt pattern (e.g., 16 holes). It is crucial to match the bolt hole count to your specific transom plate. Cross-referencing the OEM part number (909527) is the best way to ensure compatibility.

OEM vs. Aftermarket?

This listing is an aftermarket replacement (not OEM). Built to OEM-level specifications with comparable materials. Manufactured in an ISO 9002 facility, batch-inspected for consistency.

Shipping speed & cost?

We ship worldwide quickly—typical transit 5–15 days. Standard shipping is free; expedited options appear at checkout where available.

Warranty & returns?

Covered by a 1-year warranty against manufacturing defects under normal use. If issues arise, contact support with your order details. Returns are accepted within our standard window (unused & in original condition). See our policy page or reach out for instructions.

Safety & Important Info

  • Verify images/specifications vs your original part. If anything differs—even if your model appears compatible—do not purchase.
  • This is an aftermarket replacement, not an OEM component.
  • Professional installation is recommended for safety and performance.

About Sea Sierra

  • Pro-Grade Standards — We supply marine parts engineered to OEM-level tolerances and tested for real-world conditions.
  • Fast Global Fulfillment — Free standard delivery to most regions in 5–15 days.
  • Manufacturer-Direct Value — Fair pricing without compromising on materials or QC.

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