Upper Casing Gasket – Fits Yamaha 9.9HP-15HP Outboards (Replaces 63V-45113-A1-00)
Upper Casing Gasket – Fits Yamaha 9.9HP-15HP Outboards (Replaces 63V-45113-A1-00) is backordered and will ship as soon as it is back in stock.
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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
Product Details
This Upper Casing Gasket provides a direct-fit seal for the lower unit on a range of Yamaha 9.9HP to 15HP, 2-stroke outboards manufactured between 1995 and 1999, including international EMH, F, and FMH models. It ensures proper sealing between the an upper casing and the gearcase to prevent water intrusion and lubricant leaks.
It serves as a direct replacement for multiple Yamaha part numbers including 63V-45113-A1-00, 63V-45113-A0-00, and 63V-45113-01-00, as well as the Sierra 18-99150 aftermarket equivalent.
- Installation: Designed for a precise OEM fitment.
- Application: Seals the upper casing to the lower unit/gear case.
- Material: Constructed from high-quality composite gasket paper.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number | Superseded By |
|---|---|---|
| Yamaha | 63V-45113-A0-00 | 63V-45113-A1-00 |
| Yamaha | 63V-45113-01-00 | 63V-45113-A1-00 |
| Yamaha | 63V-45113-A1-00 | |
| Sierra | 18-99150 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
Fitment data covers select Yamaha Outboard and International models from 1995–1999.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| Yamaha | 9.9F (63V) [999] | 9.9 | 2-Stroke | 1995–1996 | 63V-45113-A1-00 | |
| Yamaha | 9.9F (63V) [XXX] | 9.9 | 2-Stroke | 1995–1996 | 63V-45113-A1-00 | |
| Yamaha | 9.9FMH (63V) [010] | 9.9 | 2-Stroke | 1995–1999 | 63V-45113-A1-00 | |
| Yamaha | 9.9FEMH (63V) [XXX] | 9.9 | 2-Stroke | 1996 | 63V-45113-A1-00 | |
| Yamaha | 9.9FEMH (63V) [090] | 9.9 | 2-Stroke | 1998–1999 | 63V-45113-A1-00 | |
| Yamaha | 15F (63W) [999] | 15 | 2-Stroke | 1995–1996 | 63V-45113-A1-00 | |
| Yamaha | 15F (63W) [XXX] | 15 | 2-Stroke | 1995–1996 | 63V-45113-A1-00 | |
| Yamaha | 15FMH (63W) [010] | 15 | 2-Stroke | 1995–1999 | 63V-45113-A1-00 | |
| Yamaha | 15FEMH (63W) [XXX] | 15 | 2-Stroke | 1996 | 63V-45113-A1-00 | |
| Yamaha | 15EMH (63W) [120] | 15 | 2-Stroke | 1998 | 63V-45113-A1-00 | |
| Yamaha | 15FWH (63W) [110] | 15 | 2-Stroke | 1999 | 63V-45113-A1-00 | |
| Yamaha | EMH (63V) [010] | 9.9 | 2-Stroke | 1995–1997 | 63V-45113-A1-00 | |
| Yamaha | EMH (63W) [010] | 15 | 2-Stroke | 1995–1997 | 63V-45113-A1-00 | |
| Yamaha | 15ELHU | 15 | 2-Stroke | 1996 | 63V-45113-A1-00 | |
| Yamaha | 15ELRU | 15 | 2-Stroke | 1996 | 63V-45113-A1-00 | |
| Yamaha | 15ESHU | 15 | 2-Stroke | 1996 | 63V-45113-A1-00 | |
| Yamaha | 15MLHU | 15 | 2-Stroke | 1996 | 63V-45113-A1-00 | |
| Yamaha | 15MSHU | 15 | 2-Stroke | 1996 | 63V-45113-A1-00 | |
| Yamaha | 9.9ELHU | 9.9 | 2-Stroke | 1996 | 63V-45113-A1-00 | |
| Yamaha | 9.9ELRU | 9.9 | 2-Stroke | 1996 | 63V-45113-A1-00 | |
| Yamaha | 9.9ESHU | 9.9 | 2-Stroke | 1996 | 63V-45113-A1-00 | |
| Yamaha | 9.9MLHU | 9.9 | 2-Stroke | 1996 | 63V-45113-A1-00 | |
| Yamaha | 9.9MSHU | 9.9 | 2-Stroke | 1996 | 63V-45113-A1-00 |
Technical Specs
- Product Type
- Upper Casing Gasket
- Installation
- OEM Fitment
- Material
- Gasket Material (Paper/Composite)
- Application
- Lower Unit/Gear Case
- Dimensions
- 25.3" L x 14.6" W x 0.3" H
- Weight
- 0.11 lb (0.05 kg)
- OEM Factory Part
- Yes (Yamaha)
- Aftermarket Options
- Yes (Sierra)
- Warranty
- Standard OEM or Manufacturer Warranty
What’s in the Box
- 1 x Upper Casing Gasket (63V-45113-A1-00)
Installation Notes
- Ensure the engine is off, cool, and disconnected from the power source.
- Drain the gearcase lubricant completely into an approved container.
- Carefully unbolt and remove the lower unit from the engine's upper casing.
- Remove the old, worn gasket. Thoroughly clean both mating surfaces, ensuring they are free of any old gasket residue, sealant, or debris.
- Align the new gasket onto the upper casing, making sure all bolt holes line up perfectly.
- Reinstall the lower unit, tightening the bolts in the sequence and to the torque specified in your owner’s service manual.
- Refill the gearcase with the recommended lubricant to the proper level.
- After a brief run time, check for any signs of lubricant leaks around the sealed area.
Troubleshooting & FAQ
How can I confirm this gasket fits my specific outboard model?
Your model and year should be listed in the Engine & Model Compatibility table. Always compare the part number (63V-45113-A1-00) and visual details with your existing gasket before ordering.
What are the signs of a failing upper casing gasket?
Common symptoms include a milky or cloudy appearance in your gear lube (indicating water intrusion) or visible gear oil leaking from the seam between the lower unit and upper casing.
Is any sealant or adhesive required with this gasket?
Generally, this type of composite gasket is designed to be installed dry. However, always consult your engine's official service manual for model-specific recommendations, as some older or worn surfaces may benefit from a non-hardening sealant.
How often should this gasket be replaced?
This gasket should be replaced any time the lower unit is removed for service, such as during a water pump impeller replacement or gearcase repair. It is not a routine maintenance item otherwise.
What's the difference between this part and an original Yamaha part?
This is an aftermarket part, not an OEM (Original Equipment Manufacturer) component. It is engineered to meet or exceed OEM specifications for fit, material, and function, offering comparable performance at a better value.
Is it difficult to install this gasket myself?
The task requires basic mechanical skills and tools, including a torque wrench. The most critical step is cleaning the mating surfaces properly. If you are not comfortable dropping the lower unit, we recommend professional installation.
What is the difference between OEM vs. Aftermarket parts?
This listing is an aftermarket replacement (not OEM). It is built to OEM-level specifications with comparable materials and manufactured in an ISO 9002 facility, where it is batch-inspected for consistency.
What are the shipping speed & costs?
We ship worldwide quickly—typical transit is 5–15 days. Standard shipping is free; expedited options will appear at checkout if they are available for your location.
What is the warranty and return policy?
This part is covered by a 1-year warranty against manufacturing defects under normal use. If you encounter an issue, contact our support team with your order details. Returns are accepted within our standard window, provided the item is unused and in its original condition. Please see our full 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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