Shift Shaft Bushing – Fits MerCruiser MC-I, R, MR, Alpha One & Gen II Stern Drives (Replaces 23-805041A2)
Shift Shaft Bushing – Fits MerCruiser MC-I, R, MR, Alpha One & Gen II Stern Drives (Replaces 23-805041A2) is backordered and will ship as soon as it is back in stock.
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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).
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Delivery and Shipping
Delivery and Shipping
Free standard shipping on all orders under 1 KG
Shift Shaft Bushing – Fits MerCruiser MC-I, R, MR, Alpha One & ...
Product Details
This is a bell housing Shift Shaft Bushing kit designed to fit MerCruiser stern drives. It is compatible with MC-I, R, MR, Alpha One, and Alpha One Generation 2 (Gen II) models produced up to serial number 0F094774 (approximately 1993).
This kit provides a direct replacement for MerCruiser part numbers 23-805041A2, 23-79373A1, 23-79373, and 23-45588, as well as several other aftermarket equivalents.
- Installs in the bell housing.
- Updates older MerCruiser 1, R, MR, and Alpha-I drives to the new-style shift shaft seal.
- Kit includes essential bushings and seals for a complete repair.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| MerCruiser | 23-805041A2 |
| MerCruiser | 23-79373A1 |
| MerCruiser | 23-79373 |
| MerCruiser | 23-45588 |
| Sierra | 18-2622 |
| GLM | 87561 |
| Mallory | 9-72161 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
This part is specifically for MerCruiser stern drive models.
| Brand | Model | Years | OEM Part No. | Notes |
|---|---|---|---|---|
| MerCruiser | MC-I | 1966–1991 | 23-805041A2 | |
| MerCruiser | R | 1966–1991 | 23-805041A2 | |
| MerCruiser | MR | 1966–1991 | 23-805041A2 | |
| MerCruiser | Alpha One | 1983–1990 | 23-805041A2 | |
| MerCruiser | Alpha One Gen II | Up to S/N 0F094774 (approx. 1993) | 23-805041A2 |
Technical Specs
- Product Type
- Shift Shaft Bushing Kit
- Installation
- Bell Housing
- Other Technical Attributes
- Updates older MerCruiser 1, R, MR, Alpha-I to new shift shaft seal
What’s in the Box
- 2 x Oil Seal (Replaces 26-816464 / 26-8164641)
- 1 x Large Bushing
- 1 x Small Bushing
Installation Notes
- Disconnect the boat's battery before starting work.
- Gain access to the stern drive's bell housing where the shift shaft is located.
- Carefully remove the old shift shaft seals and bushings from the housing. Avoid scratching or damaging the bore.
- Thoroughly clean the bore to remove any debris or corrosion.
- Gently press the new large and small bushings into their respective positions.
- Install the two new oil seals, ensuring they are properly seated.
- Reassemble all components in the reverse order of removal.
- Verify the shift linkage operates smoothly through all gears.
- Reconnect the battery and test functionality in the water, checking for leaks.
Troubleshooting & FAQ
Will this fit my Alpha One Gen II drive?
This kit fits Alpha One Gen II models up to serial number 0F094774 (approximately 1993). It is critical to verify your drive's serial number before purchasing to ensure compatibility.
What is the purpose of this bushing kit?
This kit repairs the seal at the point where the shift shaft enters the bell housing. It prevents water from entering the drive and causing gear lube contamination, while also ensuring the shaft can rotate smoothly.
What are the signs of a failing shift shaft bushing?
Common symptoms include water in the gear lube (milky appearance), difficulty shifting between forward, neutral, and reverse, or visible corrosion and water leakage around the shift shaft area on the bell housing.
How often should this part be replaced?
There is no fixed service interval. This component should be inspected during regular stern drive maintenance and replaced if there are any signs of leakage, corrosion, or excessive wear.
Is this the same as the original MerCruiser part?
This is an aftermarket part, not original MerCruiser. It is engineered to meet or exceed OEM specifications for fit, form, and function, providing a reliable and cost-effective alternative.
Are tools required to install this kit?
Yes, installation requires standard mechanic's tools as well as potentially a seal puller and a press or driver to properly seat the new bushings and seals without damaging them.
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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