Yamaha Piston Kit (0.50mm Oversize) – Fits Yamaha 50-70HP 2-Stroke Outboards (Replaces 6H3-11636-01-00)
Yamaha Piston Kit (0.50mm Oversize) – Fits Yamaha 50-70HP 2-Stroke Outboards (Replaces 6H3-11636-01-00) is backordered and will ship as soon as it is back in stock.
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Delivery and Shipping
Delivery and Shipping
Free standard shipping on all orders under 1 KG
Yamaha Piston Kit (0.50mm Oversize) – Fits Yamaha 50-70HP 2-Stroke ...
Product Details
This is a Yamaha Piston Kit (0.50mm Oversize) designed for a wide range of Yamaha 50HP, 60HP, and 70HP 2-stroke outboard motors manufactured between 1984 and 2005. It serves as a high-quality replacement for failed or worn pistons, specifically for engine blocks bored to a 72.5mm diameter.
It directly replaces Yamaha OEM part 6H3-11636-01-00 and Sierra 18-4093, offering a reliable and cost-effective alternative for engine rebuilds.
- Installs within the engine cylinder block.
- Kit includes piston, rings, wrist pin, and clips for a complete single-cylinder overhaul.
- Engineered for 0.50mm oversize applications.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Yamaha | 6H3-11636-01-00 |
| Sierra | 18-4093 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| Yamaha | 50G/GEO/GETO | 50 | 2-Stroke | 1984–2005 | 6H3-11636-01-00 | 0.50mm Oversize |
| Yamaha | 60F/FEDO/FEHT/FEO/FET/FETO | 60 | 2-Stroke | 1984–2005 | 6H3-11636-01-00 | 0.50mm Oversize |
| Yamaha | 60TDR/TLR-B/TR-Z | 60 | 2-Stroke | 1984–2005 | 6H3-11636-01-00 | 0.50mm Oversize |
| Yamaha | 70B/BEHDO/BEMO/BEO/BETO | 70 | 2-Stroke | 1984–2005 | 6H3-11636-01-00 | 0.50mm Oversize |
| Yamaha | 70TDR/TR | 70 | 2-Stroke | 1984–2005 | 6H3-11636-01-00 | 0.50mm Oversize |
| Yamaha | 70ETLN | 70 | 2-Stroke | 1984 | 6H3-11636-01-00 | 0.50mm Oversize |
| Yamaha | 70ETLK | 70 | 2-Stroke | 1985 | 6H3-11636-01-00 | 0.50mm Oversize |
| Yamaha | 70ETLJ | 70 | 2-Stroke | 1986 | 6H3-11636-01-00 | 0.50mm Oversize |
| Yamaha | 70ETLH | 70 | 2-Stroke | 1987 | 6H3-11636-01-00 | 0.50mm Oversize |
| Yamaha | 70ETLG | 70 | 2-Stroke | 1988 | 6H3-11636-01-00 | 0.50mm Oversize |
| Yamaha | 70ETLF | 70 | 2-Stroke | 1989 | 6H3-11636-01-00 | 0.50mm Oversize |
| Yamaha | 70ETLD | 70 | 2-Stroke | 1990 | 6H3-11636-01-00 | 0.50mm Oversize |
| Yamaha | 70TLRP/70TRP | 70 | 2-Stroke | 1991 | 6H3-11636-01-00 | 0.50mm Oversize |
| Yamaha | P60TLHP | 60 | 2-Stroke | 1991 | 6H3-11636-01-00 | 0.50mm Oversize |
| Yamaha | 70TLRQ | 70 | 2-Stroke | 1992 | 6H3-11636-01-00 | 0.50mm Oversize |
| Yamaha | P60TLHQ | 60 | 2-Stroke | 1992 | 6H3-11636-01-00 | 0.50mm Oversize |
| Yamaha | 70TLRR | 70 | 2-Stroke | 1993 | 6H3-11636-01-00 | 0.50mm Oversize |
| Yamaha | P60TLHR | 60 | 2-Stroke | 1993 | 6H3-11636-01-00 | 0.50mm Oversize |
| Yamaha | 70TLRS | 70 | 2-Stroke | 1994 | 6H3-11636-01-00 | 0.50mm Oversize |
| Yamaha | P60TLHS | 60 | 2-Stroke | 1994 | 6H3-11636-01-00 | 0.50mm Oversize |
| Yamaha | 70TLRT | 70 | 2-Stroke | 1995 | 6H3-11636-01-00 | 0.50mm Oversize |
| Yamaha | P60TLHT | 60 | 2-Stroke | 1995 | 6H3-11636-01-00 | 0.50mm Oversize |
| Yamaha | 70TLRU | 70 | 2-Stroke | 1996 | 6H3-11636-01-00 | 0.50mm Oversize |
| Yamaha | C60ELRU/C60TLRU | 60 | 2-Stroke | 1996 | 6H3-11636-01-00 | 0.50mm Oversize |
| Yamaha | P60TLHU | 60 | 2-Stroke | 1996 | 6H3-11636-01-00 | 0.50mm Oversize |
| Yamaha | 70TLRV | 70 | 2-Stroke | 1997 | 6H3-11636-01-00 | 0.50mm Oversize |
| Yamaha | C60TLRV | 60 | 2-Stroke | 1997 | 6H3-11636-01-00 | 0.50mm Oversize |
| Yamaha | P60TLHV | 60 | 2-Stroke | 1997 | 6H3-11636-01-00 | 0.50mm Oversize |
| Yamaha | 70TLRW | 70 | 2-Stroke | 1998 | 6H3-11636-01-00 | 0.50mm Oversize |
| Yamaha | C60TLRW | 60 | 2-Stroke | 1998 | 6H3-11636-01-00 | 0.50mm Oversize |
| Yamaha | P60TLHW | 60 | 2-Stroke | 1998 | 6H3-11636-01-00 | 0.50mm Oversize |
| Yamaha | 70TLRX | 70 | 2-Stroke | 1999 | 6H3-11636-01-00 | 0.50mm Oversize |
| Yamaha | C60TLRX | 60 | 2-Stroke | 1999 | 6H3-11636-01-00 | 0.50mm Oversize |
| Yamaha | P60TLHX | 60 | 2-Stroke | 1999 | 6H3-11636-01-00 | 0.50mm Oversize |
| Yamaha | 70TLRY | 70 | 2-Stroke | 2000 | 6H3-11636-01-00 | 0.50mm Oversize |
| Yamaha | C60TLRY/C70TLRY | 60/70 | 2-Stroke | 2000 | 6H3-11636-01-00 | 0.50mm Oversize |
| Yamaha | 60TLRZ/70TLRZ | 60/70 | 2-Stroke | 2001 | 6H3-11636-01-00 | 0.50mm Oversize |
| Yamaha | C60TLRZ/C70TLRZ | 60/70 | 2-Stroke | 2001 | 6H3-11636-01-00 | 0.50mm Oversize |
| Yamaha | 60TLRA/70TLRA | 60/70 | 2-Stroke | 2002 | 6H3-11636-01-00 | 0.50mm Oversize |
| Yamaha | 60TLRB/70TLRB | 60/70 | 2-Stroke | 2003 | 6H3-11636-01-00 | 0.50mm Oversize |
| Yamaha | 60TLRC/70TLRC | 60/70 | 2-Stroke | 2004 | 6H3-11636-01-00 | 0.50mm Oversize |
| Yamaha | 60TLRD | 60 | 2-Stroke | 2005 | 6H3-11636-01-00 | 0.50mm Oversize |
Technical Specs
- Product Type
- Piston Kit (0.50mm Oversize)
- Installation
- Engine Cylinder
- Piston Diameter
- 72.50mm
- Piston Height
- 76.80mm
- Wrist Pin Diameter
- 20mm
- Connection
- Wrist Pin
- Weight
- 0.42 lbs (0.19 kg)
- Fitting Type
- Engine Cylinder Block
- Other Technical Attributes
- 0.50mm Oversize (O/S)
What’s in the Box
- 1 x Piston (0.50mm Oversize) (6H3-11636-01-00)
- 1 x Piston Ring Set
- 1 x Piston Pin
- 2 x Piston Pin Clips
Installation Notes
- Disconnect the battery and ensure the engine is cool. Drain the engine oil and coolant.
- Remove the cylinder head and any other components obstructing access to the piston.
- Carefully rotate the crankshaft to move the piston to the bottom of its stroke.
- Inspect the cylinder walls for damage. Honing is required to ensure a proper seal with the new piston rings.
- Remove the old piston pin clips, wrist pin, and piston.
- Lubricate the new piston and rings with fresh engine oil. Install the rings according to the manufacturer's instructions.
- Install the new piston with the orientation mark (if present) facing the correct direction (typically the exhaust side).
- Insert the lubricated wrist pin and secure it with the new clips.
- Use a piston ring compressor to gently guide the piston into the cylinder bore.
- Reassemble all components in reverse order of removal, torquing bolts to the manufacturer's specifications.
- Refill engine oil and coolant. Reconnect the battery.
- Follow the engine service manual’s recommended break-in procedure.
Troubleshooting & FAQ
How do I know if this 0.50mm oversize piston is right for my engine?
This oversize piston is for engines where the cylinder has been machined (bored) 0.50mm larger than its standard diameter to correct for wear or damage. You must have a professional measure the cylinder bore; it must be 72.50mm for this piston to fit correctly.
What are signs of a failing piston?
Common symptoms include a noticeable loss of engine power, excessive oil consumption, blue-colored smoke from the exhaust, low compression test results, or a persistent metallic knocking or slapping sound from the engine.
Does this kit service the entire engine?
No, this kit contains parts to service one cylinder. If you are rebuilding an engine with multiple cylinders, you will need to purchase one kit per cylinder.
Is honing the cylinder necessary for installation?
Yes, absolutely. The cylinder wall must be honed to create a cross-hatch pattern. This surface allows the new piston rings to seat properly, ensuring optimal compression and heat transfer.
What is the break-in process for a new piston?
Follow the guidelines in your outboard's official service manual. Generally, it involves running the engine at varied, low-to-mid-range RPMs with no heavy load for the first few hours of operation to allow the rings to seal against the cylinder wall.
Can I reuse my old piston rings or wrist pin?
No. This kit includes a new piston, ring set, wrist pin, and clips. These components are designed to wear together. Never reuse old rings, pins, or clips with a new piston, as it can lead to premature failure and engine damage.
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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