Cylinder Head Gasket – Fits Yanmar 1GM Marine Engines (Replaces 128170-01331)
Cylinder Head Gasket – Fits Yanmar 1GM Marine Engines (Replaces 128170-01331) 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
Cylinder Head Gasket – Fits Yanmar 1GM Marine Engines (Replaces 128...
Product Details
This replacement Cylinder Head Gasket is engineered to fit the Yanmar 1GM single-cylinder marine diesel engine. It provides a reliable seal between the cylinder head and the engine block, ensuring optimal compression and performance. Note: This gasket is not compatible with 1GM10 models.
It serves as a direct replacement for Yanmar OEM part number 128170-01331.
- Installation Type: Direct replacement
- Designed for diesel fuel engines
- Ensures a precise fit and durable seal
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number | Notes |
|---|---|---|
| Yanmar | 128170-01331 | Does not fit 1GM10 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
| Brand | Model | Rated HP | Stroke | OEM Part No. | Notes |
|---|---|---|---|---|---|
| Yanmar | 1GM | 7.5 | 4-Stroke | 128170-01331 | Does not fit 1GM10 |
Technical Specs
- Product Type
- Cylinder Head Gasket
- Installation
- Direct replacement
- Fuel Type
- Diesel
- Dimensions
- 13.5" x 11.5" x 0.2"
- Warranty
- 6 months (when purchased as genuine Yanmar part)
- Other Technical Attributes
- Not compatible with 1GM10 models
What’s in the Box
- 1 x Cylinder Head Gasket (128170-01331)
Installation Notes
- Disconnect the vessel's battery and close the raw water seacock.
- Drain the engine coolant completely.
- Carefully remove the intake and exhaust manifolds, fuel lines, and any other components obstructing access to the cylinder head.
- Loosen and remove the cylinder head bolts in the sequence specified by the manufacturer's service manual.
- Lift the cylinder head off the engine block and remove the old head gasket.
- Thoroughly clean both the cylinder head and engine block surfaces, ensuring they are free of any old gasket material, carbon deposits, or debris.
- Place the new head gasket onto the engine block, ensuring correct orientation.
- Carefully reposition the cylinder head.
- Install and torque the head bolts in the correct pattern and to the specified torque values found in your engine's service manual.
- Reassemble all other components in the reverse order of removal.
- Refill the cooling system, open the seacock, and reconnect the battery.
- Start the engine and check for any coolant, fuel, or exhaust leaks.
Troubleshooting & FAQ
How do I confirm this gasket fits my Yanmar engine?
This gasket is specifically for the Yanmar 1GM model. The most reliable way to confirm fitment is by matching the OEM part number 128170-01331. It is explicitly not compatible with the 1GM10 model, so please verify your engine model plate carefully.
What are the signs of a failing cylinder head gasket?
Common symptoms include engine overheating, white smoke from the exhaust (burning coolant), loss of coolant with no visible external leak, milky or discolored engine oil (coolant contamination), or a loss of compression and power.
Is replacing a head gasket considered routine maintenance?
No, a cylinder head gasket is designed to last for many years and is not a routine replacement item. It is typically only replaced when it fails or during a major engine overhaul that requires removing the cylinder head.
Is this aftermarket gasket as good as the original Yanmar part?
This is a high-quality aftermarket part manufactured to meet or exceed original equipment manufacturer (OEM) specifications. It provides a reliable, cost-effective alternative to the genuine OEM part without sacrificing performance or durability.
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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