Starboard Piston Assembly – Fits Mercury/Mariner V-135, V-150 HP (Replaces 765-7441T32)

$115.00 $184.00

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Starboard Piston Assembly – Fits Mercury/Mariner V-135, V-150 HP (Replaces 765-7441T32) is backordered and will ship as soon as it is back in stock.

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Product Details

This is a replacement Starboard Piston Assembly – Fits Mercury/Mariner V-135, V-150 HP (Replaces 765-7441T32), designed for a range of V6 2-stroke outboard engines from Mercury, Mariner, and Force, primarily covering model years 1979 to 2005. It is a top-guided piston engineered for use in 2.0L loop charged engines.

This assembly serves as a direct aftermarket replacement for Mercury OEM parts 765-7441A32 and 765-7441T32, as well as WSM 100-30SK and ProV Marine 4000SV.

Designed for starboard (right-side) cylinder installation.
Engineered for use with connecting rod #644-818141.
Kit includes the piston, piston rings, and wrist pin for a complete assembly.

Part Number Matrix

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

Brand	Part Number
Mercury	765-7441A32
Mercury	765-7441T32
WSM	100-30SK
ProV Marine	4000SV

Engine & Model Compatibility

Confirm your engine model/year in the table below.

For Mercury/Mariner/Force engines, check your serial number to ensure it falls within the specified range for your model and year.

Model	Rated HP	Stroke	Years	OEM Part No.	Notes
V-105 Jet	105	2-Stroke	2000–Up	765-7441T32	Serial Range: 0D082000 and Up
V-135	135	2-Stroke	1979–1999	765-7441T32	Serial Range: 0A904646-0D081999, with Rod No. 644-818141
V-135	135	2-Stroke	2000–2001	765-7441T32	Serial Range: 0D082000 and Up
V-140 Jet	140	2-Stroke	Up to 1999	765-7441T32	Serial Range: None & Below - 0G760299
V-150	150	2-Stroke	1979–1999	765-7441T32	Serial Range: 0A904646-0D081999, with Rod No. 644-818141
V-150	150	2-Stroke	2000–2005	765-7441T32	Serial Range: 0D082000 and Up

Technical Specs

Product Type: Starboard (Right-Side) Piston Assembly
Piston Diameter: 3.125" (79.38 mm)
Compatibility: Mercury/Mariner/Force V6 2-Stroke Outboards
For Use With: Connecting Rod #644-818141
Package Contents: Piston, Piston Rings, Wrist Pin
Application: Loop Charged Engines
OEM Replacement: Direct replacement for Mercury/Mariner/Force 765-7441T32
Other Technical Attributes: Top-guided piston for 2.0L Mercury engines

What’s in the Box

1 x Starboard Piston Kit with Rings & Wrist Pins (Replaces 765-7441T32)

Installation Notes

Disconnect the battery and fuel supply as a safety precaution.
Disassemble the engine block to access the cylinder bank.
Carefully remove the old piston assembly from the connecting rod.
Clean the cylinder bore and connecting rod surfaces thoroughly, checking for any scoring or damage.
Install the new piston rings onto the piston, ensuring they are correctly oriented.
Lubricate the new piston, rings, and wrist pin with 2-stroke engine oil.
Attach the new piston assembly to the connecting rod using the provided wrist pin and clips.
Use a ring compressor to carefully guide the piston into the cylinder bore.
Reassemble the engine according to the manufacturer's service manual, ensuring all bolts are torqued to specification.

Troubleshooting & FAQ

How do I know if this piston fits my specific engine?

The best way to confirm is by matching your engine's model, year, and serial number against the compatibility table. This piston is for specific V6 2-stroke Mercury, Mariner, and Force engines. Pay close attention to serial number ranges and the required connecting rod part number (644-818141).

What are the signs of a failing piston?

Common signs include loss of compression in a cylinder, a knocking or rattling sound from the engine, excessive smoke from the exhaust, and reduced overall engine performance. A borescope inspection may reveal scoring on the cylinder walls or damage to the piston crown.

Is this for the starboard or port side?

This assembly is specifically for the starboard (right-hand) side of the engine. Port and starboard pistons are often not interchangeable due to wrist pin offset and ring design. Always replace with the correct side.

Can I replace just one piston?

While possible, it is generally recommended to inspect and consider replacing all pistons at the same time, especially on high-hour engines. This ensures a balanced and reliable engine rebuild. If one piston has failed, others may be worn and at risk of future failure.

What is a "loop charged" engine?

Loop charging is a method of scavenging exhaust gases from a two-stroke engine's cylinder and refilling it with a fresh fuel-air mixture. This piston is designed specifically for engines that use this system.

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

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