Bellows Expander Tool – Fits MerCruiser Alpha One, Alpha Gen II, Bravo 1/2/3 (Replaces 91-45497A1)
Bellows Expander Tool – Fits MerCruiser Alpha One, Alpha Gen II, Bravo 1/2/3 (Replaces 91-45497A1) 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
Bellows Expander Tool – Fits MerCruiser Alpha One, Alpha Gen II, Br...
Product Details
This marine Bellows Expander Tool – Fits MerCruiser Alpha One, Alpha Gen II, Bravo 1/2/3, MC-1, R-MR & Blackhawk Drives (Replaces 91-45497A1) features a scissor-style mechanism designed to stretch and install exhaust bellows during replacement. It provides a proper fit for a wide range of MerCruiser stern drives, including the Alpha One (Gen I & II), Bravo Series (1, 2, & 3), Blackhawk, MC-1, and R-MR models.
It serves as a direct interchange for MerCruiser 91-45497A1 and 8M0096108, as well as aftermarket equivalents Sierra 18-9847, GLM 90360, and Mallory 79811.
- Operates with a simple screw-lock scissor mechanism.
- Constructed from durable steel with a comfortable vinyl grip handle.
- Requires stern drive removal for proper use.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| MerCruiser | 91-45497A1 |
| MerCruiser | 8M0096108 |
| Sierra | 18-9847 |
| GLM | 90360 |
| Mallory | 79811 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
Fitment is confirmed for the following MerCruiser drive models.
| Brand | Model | Years | OEM Part No. | Notes |
|---|---|---|---|---|
| MerCruiser | Alpha One Gen I | All | 91-45497A1, 8M0096108 | |
| MerCruiser | Alpha One Gen II | All | 91-45497A1, 8M0096108 | |
| MerCruiser | Bravo One | All | 91-45497A1, 8M0096108 | |
| MerCruiser | Bravo Two | All | 91-45497A1, 8M0096108 | |
| MerCruiser | Bravo Three | All | 91-45497A1, 8M0096108 | |
| MerCruiser | Blackhawk | All | 91-45497A1, 8M0096108 | |
| MerCruiser | MC-1 | All | 91-45497A1, 8M0096108 | |
| MerCruiser | R-MR | All | 91-45497A1, 8M0096108 |
Technical Specs
- Product Type
- Bellows Expander Tool
- Installation
- Scissor-style with screw lock
- Material
- Steel with vinyl grip handle
- Compatibility
- MerCruiser Alpha One, Alpha Gen II, Bravo 1/2/3, MC-1, R-MR & Blackhawk drives
- Usage
- Used to stretch exhaust bellows through transom openings for installation
- Tool Function
- Stretches the bellows to allow proper installation through exhaust holes
- Installation Note
- Requires stern drive removal for use
What’s in the Box
- 1 x Bellows Expander Tool (Replaces 91-45497A1)
Installation Notes
- Install the new exhaust bellows securely onto the gimbal housing.
- Insert the tool and use it to stretch the bellows through the exhaust hole in the bell housing.
- Once the bellows is correctly positioned, tighten the hose clamp to secure it in place.
Note: The stern drive must be removed from the transom assembly before you can use this tool.
Troubleshooting & FAQ
What is this tool's primary function?
This tool is specifically designed to stretch the exhaust bellows on MerCruiser stern drives, allowing it to be guided and seated properly through the transom and bell housing during installation.
Do I have to remove the outdrive to replace the exhaust bellows?
Yes, complete removal of the stern drive unit is required to access and replace the exhaust bellows and to use this expander tool correctly.
How do I know if my drive model is compatible?
This tool fits MerCruiser Alpha One (Gen I and II), Bravo (One, Two, Three), Blackhawk, MC-1, and R-MR drives. Please check the compatibility table on this page to confirm your specific model.
Is this tool difficult to operate?
The tool itself is straightforward, using a scissor action controlled by a threaded rod. However, the overall job of replacing bellows is labor-intensive and requires mechanical knowledge, as the outdrive must be removed first.
What are the signs of a failing exhaust bellows?
A common sign of a failing exhaust bellows is water leaking into the bilge. You may also notice visible cracks, splitting, or deterioration of the rubber during a visual inspection of the drive unit.
Can I use this for other bellows, like the U-joint or shift cable bellows?
No, this tool is specifically designed for the exhaust bellows, which is larger and requires a different installation technique. Other bellows have their own specific installation tools and methods.
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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