Piston Kit – Fits Mercury Mariner 175-225 HP 2.4L (Replaces 100-10PCHK, 766-8667T41)
Piston Kit – Fits Mercury Mariner 175-225 HP 2.4L (Replaces 100-10PCHK, 766-8667T41) is backordered and will ship as soon as it is back in stock.
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Worry-free returns
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Delivery and Shipping
Delivery and Shipping
Free standard shipping on all orders under 1 KG
Piston Kit – Fits Mercury Mariner 175-225 HP 2.4L (Replaces 100-10P...
Product Details
This Piston Kit – Fits Mercury Mariner 175-225 HP 2.4L is engineered for Mercury and Mariner 2.4L engines ranging from 175 to 225 HP. It is specifically designed for models featuring chrome cylinders and is intended for standard bore applications.
It serves as a direct aftermarket cross-reference for OEM part numbers 100-10PCHK and 766-8667T41.
- Installation: Designed exclusively for installation in engines with chrome cylinder bores.
- Performance Coating: Features a MOS2 coating on the piston skirt to reduce friction and improve heat absorption for demanding use.
- Engineered Porting: Expertly ported to match WSM Banshee sleeves, ensuring optimal performance.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| WSM | 100-10PCHK |
| Mercury | 766-8667T41 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
For Mercury models, this kit fits various 2.4L V6 engines, including LoopCharge, XR4, and MAG II series. Note the important distinction between chrome and steel bore applications, as this kit is only for chrome bores.
For Mariner engines, this kit is compatible with all 175-225 HP models that utilize a chrome bore.
| Brand | Model | Rated HP | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|
| Mercury | 6 Cyl 3.375 Chrome Bore 2.4L | 175 | 1983–1991 | 766-8667T41 | |
| Mercury | 6 Cyl 3.375 Chrome Bore 2.4L | 200 | 1983–1990 | 766-8667T41 | |
| Mercury | 6 Cyl 3.375 Bore 2.4L | 175 | 1981–1982 | For engines with steel bore | |
| Mercury | 6 Cyl 3.375 Bore 2.4L | 200 | 1978–1982 | For engines with steel bore | |
| Mercury | 6 Cyl 3.375 Bore 2.4L | 225 | 1980–1981 | For engines with steel bore | |
| Mariner | ALL | 175-225 | 766-8667T41 | For engines with chrome bore | |
| Mercury | V-175 | 175 | 6618751-0C239552 | 766-8667T41 | LoopCharge, XR4, MAG II |
| Mercury | V-200 EFI | 200 | 9C100861-0C999999 | 766-8667T41 | LoopCharge, XR4, MAG II |
| Mercury | V-220 | 220 | 0B117316+ | 766-8667T41 | LoopCharge, XR4, MAG II |
| Mercury | V-225 | 225 | 5628028+ | 766-8667T41 | LoopCharge, XR4, MAG II |
Technical Specs
- Product Type
- Piston Kit
- Cylinder Compatibility
- For Chrome Cylinders Only
- Dimensions
- 16.5" H x 8.5" W x 9.0" L
- Weight
- 0.45 kg (1 pound)
- Coating
- MOS2 Coated for high performance
- Porting
- Ported to match WSM Banshee sleeves
Installation Notes
- Before starting, verify the new piston kit matches your old part and specifications.
- Disconnect the battery and safely relieve any pressure from the fuel system.
- Drain the engine oil and coolant completely.
- Remove the cylinder head and any other components obstructing access to the pistons.
- Carefully extract the old piston and connecting rod assembly from the cylinder.
- Crucially, confirm your engine has chrome cylinder bores. This kit is incompatible with steel bore engines and will cause damage.
- Install the new piston onto the connecting rod according to manufacturer guidelines.
- Generously lubricate the new piston, rings, and cylinder wall with engine assembly lube.
- Using a ring compressor, carefully install the new piston assembly into the cylinder, ensuring correct orientation.
- Reassemble the engine, torquing all bolts to the manufacturer's specified values.
- Refill the engine with fresh oil and coolant.
- Start the engine, let it idle, and carefully check for any fluid leaks or abnormal sounds.
Troubleshooting & FAQ
How do I know if this piston fits my engine?
Check your engine's model, year, and serial number against our compatibility table. Most importantly, you must verify your engine has a 2.4L displacement with chrome cylinder bores, as this kit will not work with steel bores.
What does "For Chrome Cylinders Only" mean?
Chrome bore cylinders have a hard, low-friction chrome plating directly on the aluminum block, while steel bore engines use a separate cast iron or steel sleeve. This piston is designed only for the material properties and tolerances of a chrome bore.
What's the purpose of the MOS2 coating?
The Molybdenum Disulfide (MOS2) coating is a high-performance, anti-friction layer applied to the piston skirt. It reduces friction, improves heat transfer, and provides extra protection during engine break-in and under extreme conditions.
Is this a standard size piston?
Yes, this is a standard bore piston kit for a 3.375" bore. It is not an oversized piston intended for cylinders that have been bored out.
What are common symptoms of a failing piston?
Signs of a bad piston include a significant loss of compression, excessive blue or white smoke from the exhaust, a knocking or rattling sound from the engine (piston slap), and poor overall performance or constant misfires.
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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