Rear Crankshaft Bearing – Fits Yanmar 1GM, 2GM & 3GM Series (Replaces 121450-02110)
Rear Crankshaft Bearing – Fits Yanmar 1GM, 2GM & 3GM Series (Replaces 121450-02110) is backordered and will ship as soon as it is back in stock.
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Worry-free returns
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Delivery and Shipping
Delivery and Shipping
Free standard shipping on all orders under 1 KG
Rear Crankshaft Bearing – Fits Yanmar 1GM, 2GM & 3GM Series (Re...
Product Details
This is a standard-size Rear Crankshaft Bearing designed for a precise fit in various Yanmar marine diesel engines, including the 1GM, 1GM10, 2GM, and 3GM series. It serves as a critical internal component to support the crankshaft and ensure smooth engine operation.
It is a direct replacement for Yanmar OEM part number 121450-02110.
- Installation: Internal engine component requiring engine disassembly.
- Material: High-strength metal housing built for durability.
- Size: This is a standard size bearing, not oversized.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Yanmar | 121450-02110 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
This component is specifically designed for Yanmar marine diesel engines listed.
| Brand | Model | Stroke | OEM Part No. | Notes |
|---|---|---|---|---|
| Yanmar | 1GM | 4-Stroke | 121450-02110 | |
| Yanmar | 1GM10 | 4-Stroke | 121450-02110 | |
| Yanmar | 2GM20 | 4-Stroke | 121450-02110 | |
| Yanmar | 2GM20F | 4-Stroke | 121450-02110 | Dual cooling |
| Yanmar | 2GM20F-YEU | 4-Stroke | 121450-02110 | |
| Yanmar | 2GM20-YEU | 4-Stroke | 121450-02110 | |
| Yanmar | 2GMLP | 4-Stroke | 121450-02110 | |
| Yanmar | 2GMSZK | 4-Stroke | 121450-02110 | |
| Yanmar | 3GM30 | 4-Stroke | 121450-02110 | |
| Yanmar | 3GM30F | 4-Stroke | 121450-02110 | Dual cooling |
| Yanmar | 3GM30F-YEU | 4-Stroke | 121450-02110 |
Technical Specs
- Product Type
- Rear Crankshaft Bearing (Main Bearing)
- Installation
- Internal engine component
- Housing Material
- Metal
- Dimensions
- Height: 8.0 cm, Width: 5.0 cm, Length: 8.0 cm
- Weight
- 0.09 kg (0.2 lb)
- Other Technical Attributes
- Standard size (not oversized)
What’s in the Box
- 1 x Rear Crankshaft Bearing (121450-02110)
Installation Notes
- Ensure the engine is off, disconnected from power, and has cooled completely.
- Drain engine oil and coolant to prevent spills.
- Follow the manufacturer's service manual to access the engine's internal components, including the crankshaft.
- Carefully remove the old rear crankshaft bearing, noting its orientation.
- Clean the mounting surface meticulously, removing all residue and debris.
- Lubricate the new bearing with clean engine oil before installation.
- Install the new bearing, ensuring it is seated correctly and aligned as per the engine manual.
- Reassemble all engine components in reverse order of disassembly.
- Refill engine oil and coolant to the recommended levels.
- Start the engine and check for any leaks or unusual noises. Professional installation is highly recommended.
Troubleshooting & FAQ
Will this bearing fit my Yanmar 3GM30F engine?
Yes, this rear crankshaft bearing is compatible with the Yanmar 3GM30F model, as well as the broader 1GM, 2GM, and 3GM series. Always verify your OEM part number is 121450-02110 for a guaranteed match.
Is this a standard or an oversized bearing?
This is a standard-size bearing. It is not oversized and is designed to fit engines with crankshafts that have not been machined down.
What are the signs of a failing crankshaft bearing?
Common symptoms include a persistent knocking or rumbling sound from the engine that increases with RPM, low oil pressure, and the presence of metallic particles in the engine oil during an oil change. Immediate inspection is recommended if these signs are present.
Is professional installation required for this part?
Yes, due to the complexity of accessing and replacing internal engine components like a crankshaft bearing, professional installation by a qualified marine mechanic is strongly recommended to ensure safety and proper engine function.
What is the difference between this aftermarket bearing and an OEM one?
This aftermarket part is engineered to meet or exceed OEM specifications for fit, form, and function. It uses comparable materials and is manufactured in a certified facility, offering a reliable, cost-effective alternative to the original manufacturer's part.
How often should crankshaft bearings be replaced?
Crankshaft bearings do not have a fixed replacement interval and are typically replaced during a major engine rebuild or when signs of wear or failure are detected. Their lifespan depends heavily on engine maintenance, lubrication, and operating conditions.
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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