Rear Cover Gasket – Fits Yanmar 2GM, 2GM(F) Series (Replaces 105225-02040)
Rear Cover Gasket – Fits Yanmar 2GM, 2GM(F) Series (Replaces 105225-02040) 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 Cover Gasket – Fits Yanmar 2GM, 2GM(F) Series (Replaces 105225...
Product Details
This Rear Cover Gasket provides a watertight seal for the main bearing housing on Yanmar 2GM20, 2GM20F, 2GM20-YEU, and 2GM20F-YEU series marine diesel engines. It ensures proper sealing between the housing assembly and the engine block, preventing costly oil leaks.
This part is a direct replacement for Yanmar OEM part number 105225-02040.
- Installs between the main bearing housing assembly and the engine block.
- Features an engine-specific design for a precise, leak-free fit.
- Engineered from durable composite materials to withstand engine heat and oil exposure.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Yanmar | 105225-02040 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
Designed for specific Yanmar marine diesel engines.
| Brand | Model | Rated HP | Stroke | OEM Part No. |
|---|---|---|---|---|
| Yanmar | 2GM20 | 20 | 4-Stroke | 105225-02040 |
| Yanmar | 2GM20F | 20 | 4-Stroke | 105225-02040 |
| Yanmar | 2GM20-YEU | 20 | 4-Stroke | 105225-02040 |
| Yanmar | 2GM20F-YEU | 20 | 4-Stroke | 105225-02040 |
| Yanmar | 2GMF | 4-Stroke | 105225-02040 |
Technical Specs
- Product Type
- Rear Cover Gasket / Main Bearing Housing Gasket
- Installation
- Between housing assembly and engine block
- Material
- Paper/composite
- Dimensions
- 15.5" L x 13.5" W x 0.1" H
- OEM Number
- 105225-02040
- Other Technical Attributes
- Engine-specific design for proper fit
What’s in the Box
- 1 x Gasket (105225-02040)
Installation Notes
- Ensure the engine is completely cool and the main battery is disconnected.
- Drain the engine oil into an appropriate container.
- Carefully remove the rear cover or main bearing housing assembly, noting the position of all fasteners.
- Thoroughly clean both mating surfaces on the engine block and the cover, removing all traces of old gasket material and sealant.
- Position the new gasket onto the engine block, aligning it with the bolt holes. Do not use any sealant unless specified by the engine manual.
- Carefully reinstall the housing assembly over the new gasket.
- Tighten the bolts in the sequence and to the torque values specified in your Yanmar service manual.
- Refill the engine with the correct grade and amount of oil, then check for any leaks around the housing before starting the engine.
Troubleshooting & FAQ
How do I know if this is the right gasket for my engine?
This gasket is designed specifically for Yanmar 2GM, 2GM(F), 2GM(F)-YEU series engines. Verify your model against our compatibility table. The surest method is to match the OEM part number 105225-02040 with the one listed in your engine's parts catalog.
What are the signs of a failing rear cover gasket?
The most common sign of a failed rear cover gasket is a persistent oil leak from the area where the engine block meets the flywheel housing. You may notice oil drips under the engine or an oily film in the bilge.
Can I reuse my old gasket after removing the cover?
No. Gaskets are designed for single use. They compress and deform to create a seal and will not seal properly if reused, leading to guaranteed leaks. Always replace the gasket whenever the component is removed.
Is any special sealant required during installation?
Generally, this type of gasket is installed dry. However, always refer to your specific Yanmar engine service manual. Some applications may call for a light application of sealant in specific areas, but applying it unnecessarily can cause installation problems.
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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