Center Main Bearing – Fits Mercury/Mariner L3/L4 65-125 HP (Replaces 42943A1)
Center Main Bearing – Fits Mercury/Mariner L3/L4 65-125 HP (Replaces 42943A1) 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
Product Details
This aftermarket Center Main Bearing – Fits Mercury/Mariner L3/L4 65-125 HP (Replaces 42943A1) is designed for 2-stroke, inline 3-cylinder (L3) and 4-cylinder (L4) engines from 1987 to 2006. It serves as a crucial internal component for the crankshaft assembly.
It provides a direct interchange for Red Rhino ME-B43, WSM 010-143, GLM 16600, and DIWEIS 42943A1, offering OEM-level fit and performance.
- Engineered as an internal engine component for crankshaft support.
- Features a durable roller bearing design.
- Designed for the center main bearing position.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Mercury/Mariner (OEM) | 42943A1 |
| Red Rhino | ME-B43 |
| WSM | 010-143 |
| GLM | 16600 |
| DIWEIS | 42943A1 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| Mercury/Mariner | Bottom Guided Connecting Rod | 70 HP | 2-Stroke | 1987–1989 | 42943A1 | Serial number B110054-C221499 |
| Mercury/Mariner | Bottom Guided Connecting Rod | 75 HP | 2-Stroke | 1990–1991 | 42943A1 | Serial number C221500-D000750 |
| Mercury/Mariner | Bottom Guided Connecting Rod | 80 HP | 2-Stroke | 1987–1989 | 42943A1 | Serial number A966142-C221499 |
| Mercury/Mariner | Bottom Guided Connecting Rod | 90 HP | 2-Stroke | 1987–1991 | 42943A1 | Serial number B10054-D000750 |
| Mercury/Mariner | Bottom Guided Connecting Rod | 100 HP | 2-Stroke | 1988–1991 | 42943A1 | Serial number C100000 & up |
| Mercury/Mariner | Bottom Guided Connecting Rod | 115 HP | 2-Stroke | 1989–1991 | 42943A1 | Serial number C100000-D000750 |
| Mercury/Mariner | Top Guided Connecting Rod | 70 HP | 2-Stroke | 1992–2000 | 42943A1 | Serial number D082000 & up |
| Mercury/Mariner | Top Guided Connecting Rod | 75 HP | 2-Stroke | 1992–1997 | 42943A1 | Serial number D082000 & up |
| Mercury/Mariner | Top Guided Connecting Rod | 80 HP | 2-Stroke | 1992–2006 | 42943A1 | Serial number D082000 & up |
| Mercury/Mariner | Top Guided Connecting Rod | 90 HP | 2-Stroke | 1992–2000 | 42943A1 | Serial number D082000 & up |
| Mercury/Mariner | Top Guided Connecting Rod | 100 HP | 2-Stroke | 1992–2000 | 42943A1 | Serial number D082000 & up |
| Mercury/Mariner | Top Guided Connecting Rod | 115 HP | 2-Stroke | 1992–2000 | 42943A1 | Serial number D082000 & up |
| Mercury/Mariner | L3/L4 | 65 JET | 2-Stroke | 1987–2006 | 42943A1 | |
| Mercury/Mariner | L3/L4 | 75-125 HP | 2-Stroke | 1987–2006 | 42943A1 |
Technical Specs
- Product Type
- Center Main Bearing
- Installation
- Internal engine component
- Dimensions
- 6.0 in x 6.0 in x 5.5 in
- Fitting Type
- Center main bearing for crankshaft
- Other Technical Attributes
- Roller bearing design
- Warranty
- Varies by manufacturer
What’s in the Box
- 1 x Center Main Bearing (42943A1)
Installation Notes
- Always consult your engine’s official service manual before beginning work.
- Disconnect the battery and ensure the engine is cool.
- Drain all necessary engine fluids, such as engine oil.
- Disassemble the engine powerhead methodically to access the crankshaft. Keep all parts organized.
- Using a bearing puller and press, carefully remove the old center main bearing from the crankshaft.
- Clean the crankshaft surface and inspect for any damage or wear.
- Press the new bearing into place, ensuring it is properly seated and aligned.
- Reassemble the engine in the reverse order of disassembly, torquing all fasteners to the manufacturer’s specifications.
Troubleshooting & FAQ
How do I know if my center main bearing is failing?
Common signs include a distinct engine knock or rumbling noise, noticeable vibration, or the presence of metal shavings in the engine oil. Reduced engine performance can also be an indicator.
Does this bearing fit both top-guided and bottom-guided connecting rods?
Yes, this center main bearing is versatile and fits engine models with both top-guided and bottom-guided connecting rods. Please consult the compatibility table to verify fitment for your specific serial number range.
What is the recommended replacement interval?
Main bearings do not have a fixed service interval. They are typically inspected and replaced during a complete engine overhaul or rebuild, or if diagnostic checks reveal signs of imminent failure.
Do I need special tools for this installation?
Yes. Proper installation is complex and requires specialized tools, including a bearing press, bearing pullers, and a calibrated torque wrench. Access to a factory service manual is critical.
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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