Thrust Bearing – Fits Yanmar 3JH/4JH Marine Engines (Replaces 129150-02931)
Thrust Bearing – Fits Yanmar 3JH/4JH Marine Engines (Replaces 129150-02931) is backordered and will ship as soon as it is back in stock.
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Delivery and Shipping
Delivery and Shipping
Free standard shipping on all orders under 1 KG
Thrust Bearing – Fits Yanmar 3JH/4JH Marine Engines (Replaces 12915...
Product Details
This standard size Thrust Bearing is engineered for a wide range of Yanmar marine and industrial diesel engines. It is designed to fit Yanmar's 3JH, 4JH, 3TNE, 3TNV, 4TNE, and 4TNV series, including both naturally aspirated and turbocharged models, ensuring broad compatibility for maintenance and rebuilds.
This component serves as a direct replacement for Yanmar part number 129150-02931.
- Installation Location: Mounts on the crankshaft to control axial movement.
- Size: Standard size (STD) for original-spec crankshafts.
- Application: Suitable for diesel-powered marine and industrial environments.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Yanmar | 129150-02931 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
Yanmar Marine Engines: Designed for 3JH and 4JH series, from the 3JH2 to the 4JH5E and their variants.
| Brand | Model | Stroke | OEM Part No. | Notes |
|---|---|---|---|---|
| Yanmar | 3JH2, 3JH2E, 3JH2L | 4-Stroke | 129150-02931 | |
| Yanmar | 3JH2-TCE, 3JH2TBE | 4-Stroke | 129150-02931 | Turbocharged variants |
| Yanmar | 3JH25A | 4-Stroke | 129150-02931 | |
| Yanmar | 3JH3, 3JH3E | 4-Stroke | 129150-02931 | |
| Yanmar | 3JH3E-YEU-E | 4-Stroke | 129150-02931 | |
| Yanmar | 3JH4E | 4-Stroke | 129150-02931 | |
| Yanmar | 3JH5AE, 3JH5E | 4-Stroke | 129150-02931 | |
| Yanmar | 4JH, 4JH-E | 4-Stroke | 129150-02931 | |
| Yanmar | 4JH-DTE, 4JH-HTE, 4JH-HTZ, 4JH-HTZAE | 4-Stroke | 129150-02931 | Turbocharged variants |
| Yanmar | 4JH-TE, 4JH-TZ | 4-Stroke | 129150-02931 | |
| Yanmar | 4JH2-DTE, 4JH2-E, 4JH2-HTE | 4-Stroke | 129150-02931 | |
| Yanmar | 4JH2-TE, 4JH2-UTE | 4-Stroke | 129150-02931 | |
| Yanmar | 4JH3-DTE, 4JH3-HTE, 4JH3-TE | 4-Stroke | 129150-02931 | |
| Yanmar | 4JH4E, 4JH4-NO | 4-Stroke | 129150-02931 | |
| Yanmar | 4JH5E | 4-Stroke | 129150-02931 |
Yanmar Industrial Engines: Compatible with 3TNE, 3TNV, 4TNE, and 4TNV series, including turbocharged models like the 4TNV84T.
| Brand | Model | Stroke | OEM Part No. | Notes |
|---|---|---|---|---|
| Yanmar | 3TNE84 | 4-Stroke | 129150-02931 | |
| Yanmar | 3TNE88 | 4-Stroke | 129150-02931 | |
| Yanmar | 3TNV88 | 4-Stroke | 129150-02931 | |
| Yanmar | 4TNE84 | 4-Stroke | 129150-02931 | |
| Yanmar | 4TNE88 | 4-Stroke | 129150-02931 | |
| Yanmar | 4TNV84T | 4-Stroke | 129150-02931 | Turbocharged variant |
| Yanmar | 4TNV88-BDHQ | 4-Stroke | 129150-02931 | |
| Yanmar | 4TNV88-BDHQ(T) | 4-Stroke | 129150-02931 | Turbocharged variant |
| Yanmar | 4TNV88-BDSA, 4TNV88-BDSA(T) | 4-Stroke | 129150-02931 | |
| Yanmar | 4TNV88-BDSAC, 4TNV88-BDSA2, 4TNV88-BDSA2T | 4-Stroke | 129150-02931 | |
| Yanmar | 4TNV88-BDWI, 4TNV88-BDYE | 4-Stroke | 129150-02931 | |
| Yanmar | 4TNV88-BNYE883, 4TNV88-BNYE883T | 4-Stroke | 129150-02931 | |
| Yanmar | 4TNV88-BPHB, 4TNV88-GNP, 4TNV88-XMS | 4-Stroke | 129150-02931 |
Technical Specs
- Product Type
- Thrust Bearing (Standard Size)
- Installation
- Crankshaft
- Fuel Type
- Diesel
- Technical Attributes
- Standard size (STD)
- Product Dimensions
- 7.0" L x 7.0" W x 0.5" H
- Box Dimensions
- 7.0" L x 7.0" W x 0.5" H
What’s in the Box
- 1 x Thrust Bearing (Replaces 129150-02931)
Installation Notes
- Ensure the engine is off, the battery is disconnected, and the engine is cool.
- Consult your engine's official service manual to access the crankshaft and main bearings.
- Carefully remove the old thrust bearing, taking note of its orientation and placement.
- Thoroughly clean the crankshaft journal and bearing housing of any old oil, sludge, or debris.
- Liberally lubricate the new thrust bearing and the crankshaft surfaces with fresh engine assembly lube or motor oil.
- Install the new thrust bearing, making sure it is seated correctly and in the proper orientation.
- Reassemble all engine components in the reverse order of disassembly, following the manufacturer's torque specifications.
- After reassembly, prime the oil system if required, and check for correct oil pressure upon first start.
Troubleshooting & FAQ
How do I know if this thrust bearing will fit my Yanmar engine?
This bearing is designed for a broad range of Yanmar engines, including the 3JH/4JH marine series and 3TNE/3TNV/4TNE/4TNV industrial series. The most reliable method is to verify your specific engine model against the "Engine & Model Compatibility" list on this page.
What are the signs of a failing crankshaft thrust bearing?
Symptoms of a worn thrust bearing include excessive crankshaft end play (a noticeable back-and-forth movement of the crankshaft), a deep knocking or rumbling sound from the bottom of the engine, or fluctuating/low oil pressure. A diagnostic check of end play is the definitive test.
Is this a standard size or oversized bearing?
This is a standard size (STD) thrust bearing. It is intended for use with a crankshaft that has not been machined or ground. Oversized bearings are only used after a crankshaft has been repaired.
When should a thrust bearing be replaced?
Thrust bearings do not have a fixed service interval. They are typically inspected and replaced during a major engine rebuild or overhaul, or when symptoms of failure become apparent. Their lifespan depends on operating conditions, oil quality, and maintenance.
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.
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