Upper Exhaust Bellow – Fits Select MerCruiser 120, 140, V6 & V8 Stern Drive Engines
Upper Exhaust Bellow – Fits Select MerCruiser 120, 140, V6 & V8 Stern Drive Engines is backordered and will ship as soon as it is back in stock.
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Delivery and Shipping
Delivery and Shipping
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Upper Exhaust Bellow – Fits Select MerCruiser 120, 140, V6 & V8...
Upper Exhaust Bellow – Fits Select MerCruiser 120, 140, V6 & V8 Stern Drive Engines is backordered and will ship as soon as it is back in stock.
Product Details
This Upper Exhaust Bellow is an aftermarket exhaust boot for select MerCruiser stern drive applications. It is designed to connect a 4-inch center-mounted riser to a 4-inch exhaust elbow on applicable MerCruiser V6 and V8 systems, and is also listed for MerCruiser 120 and 140 stern drive engines.
The bellow has a 4-inch (102 mm) inside diameter and is 4.25 inches (108 mm) long. It is sold as a single bellow; clamps and other installation hardware are not included unless separately stated by the seller.
- Upper exhaust bellow for compatible MerCruiser stern drive systems.
- 4-inch center-mounted riser to 4-inch elbow connection.
- 4-inch (102 mm) inside diameter.
- 4.25-inch (108 mm) overall length.
- Aftermarket replacement for the listed manufacturer and aftermarket reference numbers.
Part Number References
Use the following reference numbers to compare your existing upper exhaust bellow. Reference numbers do not replace confirming the engine configuration, exhaust connection, dimensions and application.
| Brand or reference type | Part number |
|---|---|
| Mercury | 32-44348T |
| Mercury | 3244348T |
| Mercury | 44348T |
| Mercury | 32-44348001 |
| Mercury | 3244348001 |
| Mercury | 44348001 |
| Sierra Marine | 18-2748 |
| Mallory Marine | 9-72805 |
| GLM | 89120 |
Engine Compatibility
The company application data lists this bellow for MerCruiser 120, MerCruiser 140, and select MerCruiser V6 and V8 stern drive engines. Exact year, serial-number and model-variant coverage is not specified in the product record, so confirm the connection arrangement and dimensions before ordering.
| Engine brand | Listed applications | Exhaust configuration | Fitment conditions |
|---|---|---|---|
| MerCruiser | 120 and 140 stern drive engines | 4-inch upper exhaust connection | Confirm the original bellow dimensions and connection arrangement. |
| MerCruiser | Select V6 and V8 stern drive engines | 4-inch center-mounted riser to 4-inch elbow | Exact model, year and serial-number coverage is not specified; verify before purchase. |
Technical Specifications
- Product type
- Upper exhaust bellow / exhaust boot
- Product quantity
- 1 bellow
- Application
- MerCruiser stern drive engines, including listed 120, 140 and select V6/V8 applications
- Connection
- 4-inch center-mounted riser to 4-inch elbow
- Inside diameter
- 4 inches (102 mm)
- Length
- 4.25 inches (108 mm)
- Material
- Not specified in the product record
- Clamps and hardware
- Not included with this single bellow unless separately stated
- Warranty
- Refer to the applicable sales and returns policy
What's in the Box
- 1 x Upper Exhaust Bellow
Not included: hose clamps, gaskets and other installation hardware unless specifically listed with your order.
Installation Notes
- Disconnect the boat battery and allow the engine and exhaust system to cool completely.
- Confirm that the replacement bellow matches the original inside diameter, length and connection arrangement.
- Loosen and remove the clamps securing the existing bellow.
- Remove the old bellow and inspect the riser, elbow and surrounding exhaust components for corrosion, damage or contamination.
- Clean the mounting surfaces without damaging the mating components.
- Position the new bellow in the same orientation as the original part.
- Install suitable clamps specified for the application. Clamps are not included with this single-bellow product.
- Tighten the clamps evenly according to the engine or clamp manufacturer's instructions; do not overtighten.
- Reconnect the battery, start the engine in a safe environment and inspect the connections for exhaust or water leaks.
Maintenance & Inspection
Inspect the upper exhaust bellow during routine service and whenever exhaust odor, water leakage, visible cracking, soft spots, deformation or clamp movement is noticed. Replace the bellow immediately if it is split, hardened, damaged or no longer seals correctly. Because service life depends on operating conditions, storage and installation, no fixed replacement interval is specified here.
Troubleshooting & FAQ
How do I confirm this bellow fits my engine?
Confirm that your engine is a MerCruiser 120, 140 or a listed select V6/V8 stern drive application. Then compare the original bellow's 4-inch inside diameter, 4.25-inch length, center-mounted riser connection and elbow connection. Also compare the manufacturer reference number where available.
Does this product fit every MerCruiser V6 or V8?
No. The application is limited to select MerCruiser V6 and V8 stern drive engines with the specified 4-inch connection arrangement. Exact model, year and serial-number coverage is not provided, so do not rely on horsepower or engine displacement alone.
Is this an upper or lower exhaust bellow?
This is an upper exhaust bellow. It connects the upper exhaust area between a compatible center-mounted riser and 4-inch elbow.
Are clamps included?
No. This listing is for one upper exhaust bellow. Clamps and other installation hardware are not included unless explicitly stated in the order details.
Is this an OEM part?
This is an aftermarket replacement. Mercury, Sierra Marine, Mallory Marine and GLM numbers shown on this page are manufacturer or reference numbers used for comparison and identification.
What are common signs of failure?
Common signs include cracks, splits, hardening, distortion, water leakage or exhaust odor in the engine compartment. Stop using the boat and inspect the exhaust system if a leak is suspected.
Can I install it myself?
Installation access varies by boat and engine layout. If you are not experienced with marine exhaust systems, have the work performed by a qualified marine technician.
Safety & Important Information
- Disconnect the battery and work only on a cool engine and exhaust system.
- Verify the engine application, connection arrangement and dimensions before purchase.
- Do not assume fitment from V6/V8 designation alone; only select applications are listed.
- Do not operate the engine if exhaust gases or water are leaking into the engine compartment.
- This is an aftermarket replacement, not an OEM component.
About Sea Sierra
- Marine Replacement Parts — Practical aftermarket components for selected marine applications.
- Application-Focused Listings — Product references and dimensions are provided to help you compare the replacement with your original part.
- Fitment Responsibility — Always confirm the engine configuration, connection arrangement and measurements before installation.
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