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Exhaust Bellows – Fits OMC Cobra & Volvo Penta SX (Replaces 3850426, 875848)

Regular price $99.99
Shipping calculated at checkout.

Exhaust Bellows – Fits OMC Cobra & Volvo Penta SX (Replaces 3850426, 875848) is backordered and will ship as soon as it is back in stock.


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You may return most new, unopened items within 7 days of delivery for a full refund. We'll also pay the return shipping costs if the return is a result of our error (you received an incorrect or defective item, etc.).

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Delivery and Shipping

Free standard shipping on all orders under 1 KG

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 aftermarket Exhaust Bellows is designed for a precise fit on a wide range of OMC Cobra V4, V6, and V8 engines from 1986–1993, as well as Volvo Penta AQ series sterndrives (SX & DP) from 1994 to the present. It provides a reliable seal for the exhaust passage between the transom assembly and the sterndrive.

It serves as a direct interchange for OEM part numbers like OMC 3850426/914036 and Volvo Penta 875848, along with aftermarket equivalents such as GLM 89190 and Sierra 18-2768.

  • Direct replacement design for straightforward installation.
  • Constructed from durable rubber/neoprene for marine environments.
  • Features a hose-type connection for a secure fit with clamps.

Part Number Matrix

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

Brand Part Number Notes
OMC 3850426 / 914036 OEM
Volvo Penta 875848 OEM
GLM 89190 Aftermarket
Sierra 18-2768 Aftermarket

Engine & Model Compatibility

Confirm your engine model/year in the table below.

For OMC, this part fits all V4, V6, and V8 Cobra models from 1986–1993 and Cobra SX models from 1994–1998.

For Volvo Penta, it is compatible with various AQ-series engines using SX and DP sterndrives from 1994 onwards.

Brand Model Rated HP Stroke Years OEM Part No. Notes
OMC Cobra (All V4, V6, V8) Various 4-Stroke 1986–1993 3850426/914036 Standard Cobra
OMC Cobra SX Various 4-Stroke 1994–1998 3850426
Volvo Penta AQ270-290, AQSP, AQDP Various 4-Stroke Up to present 875848 SX & DP drives
Volvo Penta AQ200-290 Various 4-Stroke Up to present 875848

Technical Specs

Product Type
Exhaust Bellows
Installation
Direct replacement
Connection
Hose-type connection with clamps
Housing Material
Rubber/Neoprene
Housing Color
Black
Fitting Type
Hose connection
Other Technical Attributes
Does not include flapper valves

What’s in the Box

  • 1 x Exhaust Bellows (Replaces 3850426 & 875848)

Installation Notes

  1. Ensure the engine is off and the battery is disconnected for safety.
  2. Gain clear access to the sterndrive's exhaust bellows, typically by trimming the drive up.
  3. Carefully loosen and remove the old hose clamps securing the bellows at both ends.
  4. Remove the old bellows. Inspect and thoroughly clean the mounting surfaces on the transom assembly and sterndrive to ensure a proper seal.
  5. Position the new bellows and secure it with new, correctly-sized marine-grade hose clamps.
  6. Tighten the clamps to the manufacturer's recommended torque to prevent leaks. Do not overtighten.
  7. After reassembly, run the engine with a water supply and check for any exhaust or water leaks around the new bellows.

Troubleshooting & FAQ

How do I confirm this bellows fits my specific boat?

This part is compatible with OMC Cobra (1986-1993) and Volvo Penta SX/DP (1994-present) drives. Please verify your drive model and year, and cross-reference the OEM part numbers (3850426 for OMC, 875848 for Volvo Penta) listed in our compatibility tables.

Does this exhaust bellows include the internal flapper valve?

No, this bellows does not come with an internal flapper valve. It is a direct replacement for exhaust systems that either do not require one or have a separate flapper assembly.

What are the signs of a failing exhaust bellows?

Common signs include a loud exhaust noise from the stern, water entering the bilge (especially when stationary or at low speeds), visible cracks or splits in the rubber, or a carbon monoxide alarm sounding in the cabin.

How often should I replace my exhaust bellows?

It is recommended to inspect exhaust bellows annually and replace them every 3-5 years as part of preventative maintenance, or immediately if any signs of wear, cracking, or damage are found.

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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