Front Crankshaft Bearing – Fits Yanmar 1GM, 2GM, 3GM Series (Replaces 121450-02100)
Front Crankshaft Bearing – Fits Yanmar 1GM, 2GM, 3GM Series (Replaces 121450-02100) 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.).
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Delivery and Shipping
Delivery and Shipping
Free standard shipping on all orders under 1 KG
Front Crankshaft Bearing – Fits Yanmar 1GM, 2GM, 3GM Series (Replac...
Product Details
This aftermarket Front Crankshaft Bearing – Fits Yanmar 1GM, 2GM, 3GM Series is engineered for a wide range of Yanmar marine diesel engines, including the 1GM, 2GM, and 3GM series manufactured from the 1980s to the 2000s. It is a vital crankshaft assembly component, ensuring smooth and reliable engine operation.
This part is a direct replacement for Yanmar part number 121450-02100.
- Designed for direct replacement installation.
- Constructed with a durable steel housing.
- Intended for the front position of the crankshaft assembly.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number | Notes |
|---|---|---|
| Yanmar | 121450-02100 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
This bearing is compatible with a variety of Yanmar marine and tractor engines.
| Brand | Model | OEM Part No. | Notes |
|---|---|---|---|
| Yanmar | 1GM, 1GM-L, 1GM-Y-C | 121450-02100 | Front crankshaft bearing |
| Yanmar | 1GM10 | 121450-02100 | Front crankshaft bearing |
| Yanmar | 2GM20, 2GM20F, 2GM20F-YEU, 2GM20-YEU | 121450-02100 | Front crankshaft bearing |
| Yanmar | 2GMLP | 121450-02100 | Front crankshaft bearing |
| Yanmar | 2GMSZK | 121450-02100 | Front crankshaft bearing |
| Yanmar | 3GM30, 3GM30F, 3GM30F-YEU | 121450-02100 | Front crankshaft bearing |
| Brand | Model | OEM Part No. | Notes |
|---|---|---|---|
| Yanmar | YM140, YM147, YM169, YM186, YM187 | 121450-02100 | Front main bearing |
| Yanmar | YM1401, YM1502, YM1510, YM1601, YM1602, YM1610, YM1702, YM1720D | 121450-02100 | Front main bearing |
| Yanmar | 3T72, 3T75 | 121450-02100 | Compatible engines |
Technical Specs
- Product Type
- Front Crankshaft Bearing
- Installation
- Direct Replacement
- Housing Material
- Steel
- Dimensions
- 6.5" L x 4.0" W x 6.5" H
- Weight
- 0.09 kg (0.20 lb)
- Warranty
- Manufacturer's Standard Warranty
- Other Technical Attributes
- Front position for crankshaft assembly
What’s in the Box
- 1 x Front Crankshaft Bearing (121450-02100)
Installation Notes
- Disconnect the vessel's battery and ensure the engine is off and cool.
- Drain the engine oil completely to prevent spills.
- Access the front of the crankshaft, which may require removing belts, pulleys, and the front engine cover.
- Carefully remove the old crankshaft bearing using appropriate bearing puller tools. Avoid scoring the crankshaft.
- Thoroughly clean the bearing seat and the crankshaft surface.
- Lightly lubricate the new bearing and the crankshaft with clean engine oil or a suitable assembly lube.
- Gently press the new bearing into place, ensuring it is seated evenly and correctly aligned.
- Reassemble the front engine cover, pulleys, and belts, torquing all bolts to manufacturer specifications.
- Refill the engine with the correct grade and amount of oil.
- Reconnect the battery, start the engine, and check for oil leaks and unusual noises.
Troubleshooting & FAQ
How do I confirm this bearing is the right fit for my Yanmar engine?
First, match your engine model to the compatibility list. Second, verify that your existing part number is 121450-02100. If you are unsure, consult your engine's service manual or contact us with your engine's model and serial number before purchasing.
What are the typical symptoms of a failing front crankshaft bearing?
Common signs of failure include a distinct knocking or rattling sound from the front of the engine, low oil pressure warnings, or the presence of metallic shavings in the engine oil during an oil change.
Do I need special tools for installation?
Yes, professional installation is highly recommended. You will likely need a harmonic balancer puller, a seal puller, a bearing driver set, and a torque wrench to ensure the bearing is installed without damage and all components are reassembled to factory specifications.
Should I lubricate the bearing before installation?
Absolutely. Always pre-lubricate the new bearing and the crankshaft journal with clean, high-quality engine oil or a dedicated assembly lube to prevent dry-start wear and premature failure.
How long can I expect this aftermarket bearing to last?
When installed correctly in a properly maintained engine, this bearing is designed to meet or exceed the lifespan of the original OEM part. Its service life depends on engine condition, operating hours, and adherence to maintenance schedules.
Is this part the same for marine and tractor engines?
Yes, this specific part number is used in both marine and tractor Yanmar engines as listed in the compatibility tables. However, always confirm the part number for your specific application, as usage can vary.
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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