Exhaust Bellows Expander Tool – Fits MerCruiser Alpha One Gen I/II, Bravo 1/2/3, MC-1, R-MR, Blackhawk (Replaces 91-45497A1, 91-8M0096108)
Exhaust Bellows Expander Tool – Fits MerCruiser Alpha One Gen I/II, Bravo 1/2/3, MC-1, R-MR, Blackhawk (Replaces 91-45497A1, 91-8M0096108) is backordered and will ship as soon as it is back in stock.
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Worry-free returns
Worry-free returns
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.).
You should expect to receive your refund within four weeks of giving your package to the return shipper, however, in many cases you will receive a refund more quickly. This time period includes the transit time for us to receive your return from the shipper (5 to 10 business days), the time it takes us to process your return once we receive it (3 to 5 business days), and the time it takes your bank to process our refund request (5 to 10 business days).
If you need to return an item, simply login to your account, view the order using the "Complete Orders" link under the My Account menu and click the Return Item(s) button. We'll notify you via e-mail of your refund once we've received and processed the returned item.
Delivery and Shipping
Delivery and Shipping
Free standard shipping on all orders under 1 KG
Exhaust Bellows Expander Tool – Fits MerCruiser Alpha One Gen I/II,...
Product Details
This Exhaust Bellows Expander Tool is a specialized marine tool for installing exhaust bellows on MerCruiser sterndrive units. It is designed to fit a wide range of models, including Alpha One (Gen I and Gen II), Bravo (1, 2, and 3), Blackhawk, MC-1, and R-MR drives. The tool simplifies installation by stretching the exhaust bellows, allowing it to pass easily through the exhaust hole in the bell housing for a secure connection.
This tool directly replaces MerCruiser part numbers 91-45497A1 and 91-8M0096108, as well as aftermarket equivalents from Sierra (18-9847), GLM (90360), and Mallory (79811).
- Features a manual scissor handle for controlled operation.
- Constructed from steel with a black oxide finish for durability.
- Handle includes an anti-slip function for a better grip during use.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| MerCruiser | 91-45497A1 |
| MerCruiser | 91-8M0096108 / 8M0096108 |
| Mercury | 45497A1 |
| Sierra | 18-9847 |
| GLM | 90360 |
| Mallory | 79811 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
This tool is confirmed to work with the following MerCruiser sterndrive models.
| Brand | Model | Years | OEM Part No. |
|---|---|---|---|
| MerCruiser | Alpha One Gen I | 91-45497A1 | |
| MerCruiser | Alpha One Gen II | 1991 & Up | 91-45497A1 |
| MerCruiser | Bravo 1 | 91-45497A1 | |
| MerCruiser | Bravo 2 | 91-45497A1 | |
| MerCruiser | Bravo 3 | 91-45497A1 | |
| MerCruiser | Blackhawk | 91-45497A1 | |
| MerCruiser | MC-1 | 91-45497A1 | |
| MerCruiser | R-MR | 91-45497A1 |
Technical Specs
- Product Type
- Exhaust Bellows Expander Tool
- Installation
- Manual operation with scissor handle
- Housing Material
- Steel with black oxide finish
- Housing Color
- Black
- Weight
- 0.61 kg (1.35 lbs)
- Other Technical Attributes
- Anti-slip function on scissor handle for better grip
What’s in the Box
- 1 x Exhaust Bellows Expander Tool (91-45497A1)
Installation Notes
- Ensure the engine is off and the sterndrive is in a safe, accessible position before beginning work.
- Insert the closed end of the expander tool into the new exhaust bellow.
- Firmly squeeze the scissor handles to stretch the bellow open to the required diameter.
- While keeping the bellow expanded, carefully guide it through the exhaust opening in the bell housing until it is properly seated.
- Once the bellow is in place, slowly release the pressure on the tool's handles to allow it to contract.
- Carefully remove the tool and visually inspect the bellow to confirm it is securely and evenly installed.
Troubleshooting & FAQ
Will this tool fit my specific MerCruiser model?
This tool is designed for a broad range of MerCruiser sterndrives, including Alpha One (Gen I & II), Bravo (1, 2, 3), Blackhawk, MC-1, and R-MR models. Please consult the compatibility table and verify your part number to ensure a correct fit.
How does this tool work?
The tool functions like a pair of reverse-action pliers or scissors. When you squeeze the handles, the opposite end expands, stretching the exhaust bellow. This makes it easier to install the bellow through the tight-fitting hole in the bell housing.
Is this tool necessary for installing an exhaust bellow?
While it may be possible to install a bellow without this tool, it is extremely difficult and can lead to damaging the new bellow or improper installation. This expander tool is highly recommended by professionals to ensure the job is done correctly and efficiently.
What are the signs that my old exhaust bellow has failed?
Common signs of a failed exhaust bellow include water leaking into the bilge area, a noticeable change in engine exhaust sound, or visible cracks and deterioration on the bellow itself during inspection.
Is this an OEM MerCruiser tool?
This is an aftermarket replacement part, not an original equipment manufacturer (OEM) tool. It is engineered to meet or exceed OEM specifications for fit and function, providing a reliable and cost-effective alternative.
What is the tool made of?
It is constructed from steel with a black oxide finish to resist corrosion and provide long-lasting durability in a marine environment.
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.
Payment & Security
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