Front Seal Cover Gasket – Fits Yanmar 1GM, 1GM10, 2GM, 3GM Series (Replaces 121575-01510, 121575-01511, 121575-01512, 128170-01510, 128170-01511)
Front Seal Cover Gasket – Fits Yanmar 1GM, 1GM10, 2GM, 3GM Series (Replaces 121575-01510, 121575-01511, 121575-01512, 128170-01510, 128170-01511) 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 Seal Cover Gasket – Fits Yanmar 1GM, 1GM10, 2GM, 3GM Series (...
Product Details
This high-quality Front Seal Cover Gasket is engineered for a precise fit on Yanmar Marine 1GM, 1GM10, 2GM, and 3GM series 1- and 2-cylinder diesel engines manufactured between 1977 and 2010. It creates a reliable seal between the front cover and the engine block, preventing oil leaks.
This part is a direct replacement for Yanmar OEM part number series 121575-xxxxx (121575-01510, 121575-01511, 121575-01512) and 128170-xxxxx (128170-01510, 128170-01511).
- Installs via surface mounting with fasteners.
- Made from durable composite gasket material suitable for diesel engines.
- Ensures a secure, leak-free seal for the engine's front cover assembly.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket suppliers.
| Brand | Part Number | Notes |
|---|---|---|
| Yanmar | 121575-01510 / -01511 / -01512 | Fits 1GM, 1GMY-C, 2GM, and 3GM series engines. |
| Yanmar | 128170-01510 / -01511 | Fits 1GM10 and 1GM10L models. |
Engine & Model Compatibility
Confirm your engine model and year in the table below to ensure correct fitment.
For Yanmar Marine Engines: This gasket fits several 1, 2, and 3-cylinder 4-stroke models. Note that two different part number series apply depending on your specific engine model.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| Yanmar | 1GM | 7 | 4-Stroke | 1977–1990 | 121575-01510/121575-01511/121575-01512 | Also fits 1GM-L |
| Yanmar | 1GMY-C | 7 | 4-Stroke | 1980–1990 | 121575-01510/121575-01511/121575-01512 | |
| Yanmar | 1GM10 | 9 | 4-Stroke | 1981–2005 | 128170-01510/128170-01511 | Later model uses different part number |
| Yanmar | 1GM10L | 9 | 4-Stroke | 1981–2005 | 128170-01510/128170-01511 | |
| Yanmar | 2GM20 | 18 | 4-Stroke | 1980–2003 | 121575-01510/121575-01511/121575-01512 | Includes 2GM20F, 2GM20F-YEU, 2GM20-YEU |
| Yanmar | 2GMLP | 18 | 4-Stroke | 1980–2000 | 121575-01510/121575-01511/121575-01512 | |
| Yanmar | 2GMSZK | 18 | 4-Stroke | 1980–2000 | 121575-01510/121575-01511/121575-01512 | |
| Yanmar | 3GM | 22 | 4-Stroke | 1980–1985 | 121575-01510/121575-01511/121575-01512 | Includes 3GM-D and 3GM-F variants |
| Yanmar | 3GM30 | 27 | 4-Stroke | 1983–2005 | 121575-01510/121575-01511/121575-01512 | Includes 3GM30F and 3GM30F-YEU variants |
Technical Specs
- Product Type
- Front Seal Cover Gasket
- Installation
- Surface mount with fasteners
- Fuel Type
- Diesel
- Housing Material
- Composite gasket material
- Dimensions
- 32.0" L × 16.0" W × 0.1" H
- Warranty
- Varies by aftermarket brand; typically 6 months or more.
- Other Attributes
- Used between the front cover and engine block.
What’s in the Box
- 1 x Front Seal Cover Gasket
Installation Notes
- Disconnect the negative battery terminal for safety.
- Drain the engine oil and coolant completely into appropriate containers.
- Remove any components obstructing access to the front engine cover.
- Carefully unfasten and remove the front cover.
- Remove the old gasket. Thoroughly clean both mating surfaces on the engine block and cover, ensuring they are free of old material, oil, and debris.
- Position the new gasket correctly, aligning all bolt holes.
- Reinstall the front cover and tighten the fasteners in a staggered sequence to the manufacturer's recommended torque specifications.
- Refill the engine with fresh oil and coolant.
- Reconnect the battery, start the engine, and carefully inspect for any leaks around the cover.
Troubleshooting & FAQ
How do I know which part number series (121575- vs 128170-) is right for my engine?
The 128170-series (128170-01510, 128170-01511) is specifically for the 1GM10 and 1GM10L models. The 121575-series fits the older 1GM as well as the 2GM and 3GM series engines. Please check our compatibility table and verify your engine model before ordering.
What are common signs of a failing front seal cover gasket?
The most common symptom is a persistent oil leak from the front of the engine, particularly around the seam where the front cover meets the engine block. You may notice oil drips under the engine or an oily film on the surrounding components.
Should I apply sealant to this gasket during installation?
Generally, this type of gasket is designed to be installed dry without any additional sealant. However, always consult your Yanmar engine's official service manual for model-specific instructions, as recommendations can vary.
Can I reuse my old gasket if it looks okay?
No. Gaskets are single-use components that compress and deform to create a seal. Reusing an old gasket will almost certainly result in leaks. Always use a new gasket during reassembly.
OEM vs. Aftermarket?
This listing is an aftermarket replacement (not OEM). Built to OEM-level specifications with comparable materials. Manufactured in an ISO 9001 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 and specifications against 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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