Yanmar Exhaust Gasket (128370-13201) – Fits Yanmar 2GM, 3GM Series Marine Diesel Engines
Yanmar Exhaust Gasket (128370-13201) – Fits Yanmar 2GM, 3GM Series Marine Diesel Engines is backordered and will ship as soon as it is back in stock.
Couldn't load pickup availability
Worry-free returns
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.).
You should expect to receive your refund within four weeks of giving your package to the return shipper, however, in many cases you will receive a refund more quickly. This time period includes the transit time for us to receive your return from the shipper (5 to 10 business days), the time it takes us to process your return once we receive it (3 to 5 business days), and the time it takes your bank to process our refund request (5 to 10 business days).
If you need to return an item, simply login to your account, view the order using the "Complete Orders" link under the My Account menu and click the Return Item(s) button. We'll notify you via e-mail of your refund once we've received and processed the returned item.
Delivery and Shipping
Delivery and Shipping
Free standard shipping on all orders under 1 KG
Yanmar Exhaust Gasket (128370-13201) – Fits Yanmar 2GM, 3GM Series ...
Product Details
This is a high-quality aftermarket Yanmar Exhaust Gasket (128370-13201), designed to serve as the mounting gasket for the exhaust mixing elbow assembly. It is engineered for a precise fit on Yanmar 2GM, 3GM, 3HM, and early 2YM/3YM series marine diesel engines where the elbow assembly bolts to the heat exchanger.
This part is a direct replacement for Yanmar OEM part number 128370-13201.
- Engineered for high-temperature and pressure an environment.
- Features a four-bolt flange mounting configuration.
- Ensures a secure seal between the mixing elbow and the heat exchanger.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Yanmar | 128370-13201 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| Yanmar | 1GMYS | 128370-13201 | ||||
| Yanmar | 2GM | 4-Stroke | 128370-13201 | |||
| Yanmar | 2GM20 | 15 | 4-Stroke | 128370-13201 | ||
| Yanmar | 2GM20F | 15 | 4-Stroke | 1980–1983 | 128370-13201 | |
| Yanmar | 2GMF | 15 | 4-Stroke | 1980–1983 | 128370-13201 | |
| Yanmar | 2YM15 | 15 | 4-Stroke | 128370-13201 | Early models with 5/8 hose fitted only | |
| Yanmar | 3GM | 4-Stroke | 128370-13201 | |||
| Yanmar | 3GM30 | 4-Stroke | 128370-13201 | |||
| Yanmar | 3GM30F | 4-Stroke | 128370-13201 | |||
| Yanmar | 3GMD | 4-Stroke | 128370-13201 | |||
| Yanmar | 3GMF | 4-Stroke | 128370-13201 | |||
| Yanmar | 3GMFH | 4-Stroke | 128370-13201 | |||
| Yanmar | 3HM | 4-Stroke | 128370-13201 | |||
| Yanmar | 3HM35 | 4-Stroke | 128370-13201 | |||
| Yanmar | 3YM20 | 20 | 4-Stroke | 128370-13201 | Early models with 5/8 hose fitted only | |
| Yanmar | 3YM30 | 30 | 4-Stroke | 128370-13201 | Early models with 5/8 hose fitted only |
Technical Specs
- Product Type
- Exhaust Mixing Elbow Gasket
- Material
- High-temperature and pressure-resistant material
- Product Dimensions
- 12.0" L × 10.0" W × 0.1" H
- Mounting
- 4-bolt flange
- Compatibility
- Indirect fresh water cooled 2/3GM, all 3HM, some direct raw water cooled 3GM, early 2/3YM with 5/8 hose fitted
What’s in the Box
- 1 × Exhaust Mixing Elbow Gasket (128370-13201)
Installation Notes
- Ensure the engine is completely cool and disconnect the battery.
- Close the raw water seacock and drain the cooling system as needed.
- Carefully unbolt the exhaust mixing elbow from the heat exchanger, taking note of all connected hoses.
- Remove the old gasket and thoroughly clean both mating surfaces. Ensure they are free of old gasket material, corrosion, and debris.
- Position the new gasket, aligning it with the bolt holes.
- Re-install the exhaust mixing elbow, tightening the bolts in a star pattern to the manufacturer's recommended torque specifications.
- Reconnect all hoses, open the seacock, and check for leaks after starting the engine.
Troubleshooting & FAQ
How do I know if this gasket fits my Yanmar engine?
This gasket fits a specific range of Yanmar engines, including the 2GM, 3GM, 3HM, and early 2YM/3YM series. The most reliable method is to match your existing part number to 128370-13201. Always check the compatibility table and notes, especially for YM series engines, which have specific fitment requirements.
What are the signs of a failing exhaust gasket?
Common signs include water or exhaust soot leaking from the joint between the mixing elbow and heat exchanger, a noticeable drop in engine cooling performance, or an unusual hissing sound from the engine bay. If you see salt crystals or rust streaks around the flange, the gasket has likely failed.
Will this gasket fit my 2YM15 or 3YM30 engine?
It may, but only on early models that were equipped with a 5/8" water hose fitting on the mixing elbow. Later models use a different configuration. Please verify your specific engine's setup before ordering.
Is this gasket reusable?
No. This is a single-use, crush-style gasket. It is designed to be compressed once to create a seal. Reusing it will likely result in leaks and potential engine damage.
What's the difference between this aftermarket gasket and a genuine Yanmar part?
Functionally, there is no difference. Our aftermarket gaskets are manufactured to meet or exceed OEM specifications using comparable high-temperature materials. They are produced in an ISO 9002 certified facility and undergo strict quality control to ensure reliable 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
Payment methods
Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.
