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Bonnet Gasket – Fits Yanmar 2TNV70 Series (Replaces 119415-11310)

Regular price $35.00

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Product Details

This Bonnet Gasket provides a precision seal for Yanmar 2TNV70 series diesel engines, including models 2TNV70-APK, 2TNV70-ASG, and 2TNV70-HGB2BT. It is also compatible with the Yanmar 2YM15 model, where it functions as a rocker cover gasket.

It serves as a direct, reliable aftermarket replacement for Yanmar OEM part number 119415-11310.

  • Easy Installation: Designed for direct replacement without modification.
  • Application: Used for the cylinder head & bonnet assembly on 2TNV70 engines and as a rocker cover gasket on 2YM15 engines.
  • Fuel Compatibility: Specifically for use in diesel engine applications.

Part Number Matrix

Use this matrix to confirm equivalent references across OEM and aftermarket.

Brand Part Number
Yanmar 119415-11310

Engine & Model Compatibility

Confirm your engine model/year in the table below.

Brand Model OEM Part No. Notes
Yanmar 2TNV70-APK 119415-11310 Cylinder head & bonnet application
Yanmar 2TNV70-ASG 119415-11310 Cylinder head & bonnet application
Yanmar 2TNV70-HGB2BT 119415-11310 Cylinder head & bonnet application
Yanmar 2YM15 119415-11310 Rocker cover gasket application

Technical Specs

Product Type
Bonnet Gasket
Installation
Direct replacement
Fuel Type
Diesel
Other Technical Attributes
Used in cylinder head & bonnet assembly
Product Dimensions
15.0" L x 13.0" W x 0.3" H
Warranty
Manufacturer defect warranty (when purchased from authorized dealer)

What’s in the Box

  • 1 x Gasket, Bonnet (Replaces 119415-11310)

Installation Notes

  1. Ensure the engine is off and completely cool before beginning work. Disconnect the negative battery terminal for safety.
  2. Thoroughly clean the engine block and bonnet mating surfaces. Remove all traces of old gasket material, oil, and debris.
  3. Carefully position the new bonnet gasket, ensuring all bolt holes and fluid passages align perfectly.
  4. Reinstall the bonnet cover. Tighten the bolts in the sequence and to the torque values specified in your engine's service manual.
  5. After reassembly, reconnect the battery, start the engine, and carefully inspect for any oil leaks around the bonnet area.

Troubleshooting & FAQ

How do I confirm this gasket fits my Yanmar engine?

This gasket fits Yanmar 2TNV70 series models (2TNV70-APK, 2TNV70-ASG, 2TNV70-HGB2BT) and the 2YM15 model. The most reliable way to confirm fitment is to match your old part's number to the replacement number, 119415-11310. Always visually compare your old part to our photos.

Is this a bonnet gasket or a rocker cover gasket?

It serves both purposes depending on the engine. For the Yanmar 2TNV70 series, it is used as a bonnet gasket. For the Yanmar 2YM15, it functions as a rocker cover gasket.

Do I need to use sealant with this gasket?

In most cases, this gasket is designed for a dry installation. Applying sealants can sometimes interfere with proper sealing. However, always defer to the specific instructions in your engine's official service manual.

What are the signs of a failing bonnet gasket?

The most common symptom is a visible oil leak around the seam between the cylinder head and the bonnet or rocker cover. A dirty, oil-caked engine in this area is a strong indicator that the gasket needs replacement.

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.
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