Shift Lever Kit – Fits MerCruiser MC-I, R, MR, Alpha One, Alpha One Gen 2 (Replaces 45518T1)
Shift Lever Kit – Fits MerCruiser MC-I, R, MR, Alpha One, Alpha One Gen 2 (Replaces 45518T1) 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
Shift Lever Kit – Fits MerCruiser MC-I, R, MR, Alpha One, Alpha One...
Product Details
This high-quality Shift Lever Kit is designed for MerCruiser sterndrive units, including the MC-I, R, MR, Alpha One, and Alpha One Generation 2 series. It is compatible with drives manufactured from 1983 to the present with serial numbers 6225577 and up.
The kit serves as a direct aftermarket replacement for multiple part numbers, including Mercury 45518T1, 45518A3, GLM 21144, Sierra 18-2622, and Mallory 9-72161.
- Installs as a direct OEM-equivalent replacement.
- Constructed from durable cast iron (lever) and brass (bushings).
- Kit includes updated style seals for improved durability and performance.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Mercury | 45518T1 |
| Mercury | 45518A3 |
| Mercury | 23-805041A2 |
| Mercury | 23-79373A1 |
| Mercury | 23-79373 |
| Mercury | 23-45588 |
| GLM | 21144/87561 |
| Sierra | 18-2622 |
| Mallory | 9-72161 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
This component is designed specifically for MerCruiser sterndrives. Please check your serial number to ensure correct fitment.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| MerCruiser | MC-I | All | 1983–1990 | 45518T1 | Serial numbers 6225577 through 0D469858 | |
| MerCruiser | R | All | 1983–1990 | 45518T1 | Serial numbers 6225577 through 0D469858 | |
| MerCruiser | MR | All | 1983–1990 | 45518T1 | Serial numbers 6225577 through 0D469858 | |
| MerCruiser | Alpha One | All | 1983–1990 | 45518T1 | Serial numbers 6225577 through 0D469858 | |
| MerCruiser | Alpha One Gen 2 | All | 1991–present | 45518T1 | Serial numbers beginning with 0D469859 and up |
Technical Specs
- Product Type
- Shift Lever Kit
- Installation
- Direct OEM replacement
- Connection
- Mechanical shift connection
- Housing Material
- Cast iron (shift lever), brass (bushings)
- Housing Color
- Black/metallic
- Dimensions
- 25.4 mm × 25.4 mm (1" × 1")
- Weight
- 127 g (4.48 oz)
- Fitting Type
- Direct-fit sterndrive component
- Other Technical Attributes
- Includes updated style seals for improved durability
What’s in the Box
- 1 x Shift Lever Assembly (45518A3)
- 1 x Large Bushing
- 1 x Small Bushing
- 2 x Oil Seals
Installation Notes
- Disconnect the battery and ensure the sterndrive is in a safe, stable position for service.
- Access the upper shift shaft assembly area, which may require removing the drive unit.
- Carefully extract the old shift lever, bushings, and seals, noting their original positions.
- Thoroughly clean all mating surfaces of debris, sealant, and any corrosion.
- Install the new oil seals and bushings, ensuring they are correctly seated in the housing.
- Position the new shift lever assembly and confirm it moves smoothly.
- Reassemble all components, torque bolts to manufacturer specifications, and test the shifting mechanism before water trials.
Troubleshooting & FAQ
How do I confirm this kit fits my specific MerCruiser drive?
Check your drive's serial number. This kit fits drives with serial numbers from 6225577 to present, covering MC-I, R, MR, Alpha One, and Alpha One Gen 2 models. Refer to the compatibility table for detailed year and serial number breaks.
What are common signs that my shift lever needs replacement?
Symptoms of a worn shift lever or bad seals include difficulty shifting into forward or reverse, a loose or sloppy feeling in the shift mechanism, or water leaking into the gear lube from the upper drive unit.
Does this kit include the "updated" style seals?
Yes, this kit includes the newer, more durable style of oil seals for improved longevity and sealing performance compared to older original parts.
Is any special grease or sealant needed for installation?
We recommend using a high-quality marine grease on the bushings and shaft during assembly. Depending on your drive model, a sealant may be required on mating surfaces to ensure a watertight seal.
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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