Crankshaft Assembly – Fits Yamaha 75-90HP 3-Cylinder Outboard (Replaces 688-11411-00/688-11411-01)

Product Details

This aftermarket Crankshaft Assembly – Fits Yamaha 75-90HP 3-Cylinder Outboard is engineered as a direct-fit replacement for a range of Yamaha 2-stroke 75HP, 80HP, 85HP, and 90HP outboard engines (1984–2006+). It is designed to restore original engine performance and integrity, ensuring reliable operation out on the water.

This assembly serves as a direct interchange for Yamaha part numbers 688-11411-00, 688-11411-01, and 688-11411-01-00, as well as aftermarket equivalents like Osaka Marine 688C and Sierra 850-325.

• Designed for straightforward OEM-spec replacement.
• Constructed from durable steel/metal alloy.
• Features anti-rust protection for enhanced corrosion resistance in marine environments.

Part Number Matrix

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

Engine & Model Compatibility

Confirm your engine model/year in the table below.

Technical Specs

Product Type

Crankshaft Assembly

Installation

OEM Replacement

Fuel Type

2-Stroke Gasoline

Housing Material

Steel/Metal Alloy

Dimensions

49.0" L x 20.0" W x 18.0" H

Weight

Approx. 24.2 lbs (11 kg)

Warranty

Manufacturer dependent (typically 1 year)

Other Technical Attributes

3-cylinder design, anti-rust protection, high elasticity and corrosion resistance

What’s in the Box

• 1 x Crankshaft Assembly (Replaces 688-11411-00/688-11411-01)

Installation Notes

1. Safely disconnect the battery, fuel lines, and all electrical connections to the powerhead.
2. Remove the engine cowlings, flywheel, and stator assembly to access the powerhead.
3. Carefully disassemble the powerhead according to the manufacturer's service manual to expose the crankshaft.
4. Remove the old crankshaft, taking note of the orientation of all bearings, seals, and connecting rods.
5. Thoroughly clean all mating surfaces and inspect for any wear or damage.
6. Lubricate and install the new crankshaft assembly, ensuring all bearings and seals are correctly seated.
7. Reassemble the powerhead, torquing all fasteners to the specified values in the correct sequence.
8. Reinstall the stator, flywheel, and all other components in reverse order of removal.
9. Reconnect all electrical and fuel lines.
10. Prime the fuel system and check for leaks before attempting to start the engine.

Troubleshooting & FAQ

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.