Mercruiser Piston Standard Kit – Fits Mercruiser Inboard Engines (Replaces 759-806661A7, 806661A3, 806661A7)
Mercruiser Piston Standard Kit – Fits Mercruiser Inboard Engines (Replaces 759-806661A7, 806661A3, 806661A7) is backordered and will ship as soon as it is back in stock.
Couldn't load pickup availability
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
Mercruiser Piston Standard Kit – Fits Mercruiser Inboard Engines (R...
Product Details
This Mercruiser piston standard kit is engineered for a precise fit in Mercruiser inboard marine engines. It delivers reliable performance and durability, making it an ideal choice for engine rebuilds, replacements, or performance upgrades requiring standard bore pistons.
This component serves as a direct replacement for Mercruiser part numbers 759-806661A7, 806661A3, and 806661A7.
- Designed for a direct OEM-level fit and installation.
- Meets specifications for standard bore size applications.
- Suitable for gasoline-powered Mercruiser inboard engines.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Mercruiser | 759-806661A7 |
| Mercruiser | 806661A3 |
| Mercruiser | 806661A7 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|
Technical Specs
- Product Type
- Piston Standard Kit
- Installation
- Direct OEM replacement
- Fuel Type
- Gasoline
- Dimensions
- 5.38 cm × 5.38 cm × 5.38 cm
- Weight
- 2.64 kg (5.82 lb)
- Bore Size
- Standard bore size (not oversized)
Installation Notes
- Disconnect the battery and safely drain all engine fluids (oil, coolant).
- Remove the cylinder head and oil pan to gain access to the piston and connecting rod assemblies.
- Carefully mark and remove the old piston and connecting rod assembly from the cylinder.
- Install the new piston onto the connecting rod, ensuring correct orientation as per the engine service manual.
- Using a piston ring compressor, carefully guide the new piston assembly into the cylinder bore.
- Install the connecting rod cap and torque the bolts to the manufacturer’s specified values.
- Continue reassembly in the reverse order of disassembly.
- Refill the engine with the correct type and amount of oil and coolant.
- Reconnect the battery, start the engine, and check for leaks and proper operation.
Troubleshooting & FAQ
How do I know if this piston kit fits my Mercruiser engine?
To ensure compatibility, cross-reference your engine’s original part number with those listed in our Part Number Matrix. It is also crucial to visually compare the product images and specifications against your existing part before purchase.
Is this a standard or oversized piston?
This is a standard bore size piston kit. It is not oversized and should be used in cylinders that have not been bored out. Please verify your cylinder bore measurement before ordering.
What are common signs that my engine pistons need replacement?
Typical symptoms of piston failure include excessive oil consumption, blue-colored smoke from the exhaust, a noticeable loss of engine compression, and persistent knocking or rattling sounds originating from the engine block.
Do I need special tools for installation?
Yes, proper piston installation requires specialized engine tools, including a piston ring compressor, a precision torque wrench, and feeler gauges. Due to the complexity, we strongly recommend professional installation by a qualified marine mechanic.
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
Payment methods
Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.
