Skeg Guard – Fits MerCruiser Alpha One 1985-1990 (Replaces 27021)
Skeg Guard – Fits MerCruiser Alpha One 1985-1990 (Replaces 27021) 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
Skeg Guard – Fits MerCruiser Alpha One 1985-1990 (Replaces 27021)
Product Details
This marine-grade Stainless Steel Skeg Guard for Mercury MerCruiser Alpha One 1985–1990 offers robust protection for MerCruiser Alpha 1 Gen 1 sterndrives. Made from mirror-polished 316 stainless steel, it is designed to either protect your original skeg or repair a broken one, requiring only 2–3 inches of the original skeg to remain for secure installation.
It serves as a direct replacement for MerCruiser part 27021 and cross-references with GlückMarine 27021, sevencow 27021-TP1, and VT-MOTOR 27021.
- Installs in approximately 10 minutes with the included bolt-on hardware kit.
- Constructed from tough, 1.6 mm thick 316 stainless steel for superior corrosion resistance.
- Features a built-in drain hole to prevent water accumulation, freezing, and corrosion.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| MerCruiser | 27021 |
| GlückMarine | 27021 |
| sevencow | 27021-TP1 |
| VT-MOTOR | 27021 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
This skeg guard is designed for Mercury and MerCruiser Alpha One (Gen 1) sterndrive applications from 1985 through 1990.
| Brand | Model | Rated HP | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|
| MerCruiser | Alpha One Gen 1 | All | 1985–1990 | 27021 | Sterndrive application |
| Mercury | Alpha 1 | All | 1985–1990 | 27021 | Sterndrive application |
Technical Specs
- Product Type
- Skeg Guard/Protector
- Application
- Protection or repair of damaged skegs
- Installation
- Bolt-On
- Material
- Marine-Grade 316 Stainless Steel
- Finish
- Mirror-Polished
- Thickness
- 1.6 mm (1/16")
- Weight
- 0.5 kg (1.1 lbs)
- Design Features
- Drain hole to prevent corrosion and water freezing
- Minimum Skeg Remaining
- 50–76 mm (2–3")
- Installation Time
- Approximately 10 minutes
- Warranty
- 1 Year
What’s in the Box
- 1 x Skeg Guard (27021)
- 2 x Hex Wrench
- 2 x Female Locking Screws
- 2 x Big Male Locking Screws
- 2 x Small Male Locking Screws
- 1 x Loctite 262 (if purchased from certain retailers)
Installation Notes
Installation is straightforward and takes about 10 minutes. Ensure you have at least 2–3 inches (50–76 mm) of the original skeg remaining. Clean the skeg thoroughly, slide the skeg guard on, and tap it into place. Secure it using the included locking screws and hex wrenches. Applying the included Loctite to the screw threads is highly recommended for a secure, vibration-resistant fit.
Troubleshooting & FAQ
Will this skeg guard fit my MerCruiser Alpha One Gen 2?
No, this guard is specifically designed for the Alpha One Gen 1 sterndrives from 1985–1990. It will not fit Gen 2 models. Always verify your drive model and year before purchasing.
How much of my original skeg needs to be left for this to work?
You need a minimum of 2 to 3 inches (50 to 76 mm) of the original skeg for this guard to mount securely. It is designed to cover and protect, or repair, the bottom portion of the skeg.
Is drilling required for installation?
No, this is a bolt-on kit. The guard clamps onto the existing skeg using the provided hardware, requiring no drilling or special tools beyond the included hex wrenches.
What is the benefit of the drain hole?
The drain hole at the bottom prevents water from getting trapped inside the guard. This helps prevent corrosion and protects against damage from water freezing and expanding in cold climates.
How do I maintain the skeg guard?
The 316 stainless steel is highly resistant to corrosion. Simply rinse it with fresh water after use in saltwater environments. Periodically check that the mounting screws remain tight.
What are the signs that my old skeg needs to be repaired or protected?
Visible damage such as cracks, chips, or a significant portion broken off are clear indicators. Even minor damage can affect handling and performance. Installing a skeg guard can prevent further damage or repair an already damaged skeg.
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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