Main Bearing – Fits Volvo Penta Diesel Engines (Replaces 20867751, 85103708)
Main Bearing – Fits Volvo Penta Diesel Engines (Replaces 20867751, 85103708) 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
Main Bearing – Fits Volvo Penta Diesel Engines (Replaces 20867751, ...
Product Details
This genuine Volvo Penta Main Bearing – Fits Volvo Penta Diesel Engines (Replaces 20867751, 85103708), with OEM part number 20867751, is a factory original equipment item designed for various Volvo Penta diesel engines, including the D9A2L MH model. It ensures reliable performance and fitment as specified by the manufacturer.
This component is the direct replacement for the superseded Volvo Penta part number 85103708.
- Designed for engine-specific installation in diesel-powered applications.
- This is an oversized bearing (O.S=0.25mm), intended for use after crankshaft machining.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number | Superseded By |
|---|---|---|
| Volvo Penta | 85103708 | 20867751 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
For Volvo Penta engines, verify your model and required part number match the details listed to ensure proper fitment.
| Brand | Model | Stroke | OEM Part No. | Notes |
|---|---|---|---|---|
| Volvo Penta | D9A2L MH | 4-Stroke | 20867751 | Supersedes 85103708 |
Technical Specs
- Product Type
- Main Bearing
- Installation
- Engine-specific
- Fuel Type
- Diesel
- Product Dimensions
- 16.5" L x 8.0" W x 5.0" H
- Other Technical Attributes
- O.S=0.25mm (oversized)
What’s in the Box
- 1 x Main Bearing (20867751)
Installation Notes
Installation must be performed by a qualified marine engine technician. Always refer to the official Volvo Penta service manual for your specific engine model. Proper cleaning, lubrication, and torque specifications are critical for engine safety and longevity. This is an oversized bearing, so crankshaft journal measurements must be confirmed before installation.
Troubleshooting & FAQ
How do I know if this oversized bearing is correct for my engine?
Oversized bearings are used when the crankshaft has been machined (ground) to a smaller diameter during a rebuild. You must measure your crankshaft journals to confirm if a 0.25mm oversized bearing is required. Consult your service manual or a professional mechanic.
What are the signs of a failing main bearing?
Common symptoms include a knocking or rumbling sound from the engine, low oil pressure, and the presence of metallic particles in the engine oil. Immediate inspection is recommended if you notice these signs.
Is this part the same as Volvo Penta 85103708?
Yes, this part (20867751) is the official factory replacement that supersedes the older part number 85103708. It serves as a direct-fit upgrade.
What is the purpose of an oversized bearing?
An oversized (O.S.) bearing compensates for material removed from the crankshaft journal during resurfacing. This ensures that the correct oil clearance is maintained, which is critical for engine lubrication and performance.
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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