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Upper Casing Gasket – Fits Yamaha 50HP 60HP 70HP Outboards (Replaces 6H3-45113-A0, 6H3-45113-00, 6H3-45113-A1)

Regular price $0.00

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

Free standard shipping on all orders under 1 KG

If you have any questions, feel free to email us at info@sierramarines.com, and we’ll get back to you within 20–36 hours.

Product Details

This aftermarket Upper Casing Gasket – Fits Yamaha 50HP 60HP 70HP Outboards provides a reliable seal for the upper casing assembly on select Yamaha 2-stroke outboard motors manufactured between 1984 and 1994.

It serves as a direct interchange for Yamaha OEM part numbers 6H3-45113-A0-00, 6H3-45113-A0, 6H3-45113-00, and 6H3-45113-A1.

  • Engineered for direct replacement installation.
  • Designed for gasoline-fueled 2-stroke outboard engines.
  • Mounts securely between upper casing sections to prevent leaks.

Part Number Matrix

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

Brand Part Number
Yamaha 6H3-45113-A0-00
Yamaha 6H3-45113-A0
Yamaha 6H3-45113-00
Yamaha 6H3-45113-A1

Engine & Model Compatibility

Confirm your engine model/year in the table below.

Compatible with the following Yamaha outboard models:

Brand Model Rated HP Stroke Years OEM Part No. Notes
Yamaha 70ETLN 70 2-Stroke 1984 6H3-45113-A0 UPPER CASING
Yamaha 70ETLK 70 2-Stroke 1985 6H3-45113-A0 UPPER CASING
Yamaha 70ETLJ 70 2-Stroke 1986 6H3-45113-A0 UPPER CASING
Yamaha 70ETLH 70 2-Stroke 1987 6H3-45113-A0 UPPER CASING
Yamaha 70ETLG 70 2-Stroke 1988 6H3-45113-A0 UPPER CASING
Yamaha 70ETLF 70 2-Stroke 1989 6H3-45113-A0 UPPER CASING
Yamaha 70ETLD 70 2-Stroke 1990 6H3-45113-A0 UPPER CASING
Yamaha 70TLRP 70 2-Stroke 1991 6H3-45113-A0 UPPER CASING
Yamaha 70TRP 70 2-Stroke 1991 6H3-45113-A0 UPPER CASING
Yamaha P60TLHP 60 2-Stroke 1991 6H3-45113-A0 UPPER CASING
Yamaha 70TLRQ 70 2-Stroke 1992 6H3-45113-A0 UPPER CASING
Yamaha P60TLHQ 60 2-Stroke 1992 6H3-45113-A0 UPPER CASING
Yamaha 70TLRR 70 2-Stroke 1993 6H3-45113-A0 UPPER CASING
Yamaha P60TLHR 60 2-Stroke 1993 6H3-45113-A0 UPPER CASING
Yamaha 70TLRS 70 2-Stroke 1994 6H3-45113-A0 UPPER CASING
Yamaha 70TRS 70 2-Stroke 1994 6H3-45113-A0 UPPER CASING
Yamaha P60TLHS 60 2-Stroke 1994 6H3-45113-A0 UPPER CASING

Technical Specs

Product Type
Upper Casing Gasket
Installation
Direct replacement
Fuel Type
Gasoline
Connection
Mounts between upper casing sections
Dimensions
28.0" L x 18.0" W x 3.0" H
Fitting Type
Direct fit
Other Technical Attributes
For 2-stroke outboard engines

What’s in the Box

  • 1 x Upper Casing Gasket (Replaces 6H3-45113-A0-00, 6H3-45113-A0, 6H3-45113-00, 6H3-45113-A1)

Installation Notes

  1. Ensure the engine is turned off and the battery is disconnected for safety.
  2. Drain any necessary fluids, such as engine oil or coolant, to prevent spills.
  3. Carefully disassemble the components required to access the upper casing gasket.
  4. Remove the old gasket and thoroughly clean both mating surfaces of any residue or old sealant.
  5. Position the new gasket correctly on the clean surface, ensuring all bolt holes align.
  6. Reassemble the engine components in the reverse order of disassembly.
  7. Torque all bolts to the manufacturer's specified values. Do not overtighten.
  8. Refill any drained fluids and reconnect the battery.
  9. Start the engine and carefully inspect for any signs of leaks around the new gasket.

Troubleshooting & FAQ

Which Yamaha engines does this gasket fit?

This gasket fits a specific range of Yamaha 60HP and 70HP 2-stroke outboard models from 1984 to 1994. While the title mentions 50HP, we have only verified compatibility for 60HP and 70HP models. Always check the detailed compatibility table on this page to confirm your exact engine model and year before ordering.

How do I know if my upper casing gasket is failing?

Common signs of a worn or failing gasket include visible oil or water leaks around the seam between the upper casing sections, engine overheating due to coolant loss, or a noticeable decrease in engine performance.

Do I need to use sealant with this gasket?

This gasket is typically designed to be installed dry. However, we always recommend consulting your engine’s official service manual for model-specific instructions regarding the use of supplemental sealants.

Is this part a direct replacement for my original gasket?

Yes, this is a direct-fit aftermarket part designed to replace Yamaha OEM numbers 6H3-45113-A0, 6H3-45113-00, 6H3-45113-A1, and 6H3-45113-A0-00. It is engineered to match the form and function of the original component.

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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