Used 1999 Yamaha 90 HP 2-Stroke Outboard Motor – Compression Tested – Freshwater Run

Description

Used 1999 Yamaha 90 HP 2-Stroke Outboard Motor – Compression Tested – Freshwater Run is available from Machinery Store. Explore this Yamaha marine engine’s configuration, performance features, condition and included equipment below.

Engine Overview

The 1999 Yamaha 90 HP 2-Stroke Outboard Motor is a proven and reliable Yamaha powerplant offering excellent value for boat owners looking for an affordable repower option.

This used JDM Yamaha 90 HP has spent its life in freshwater only and is listed with approximately 100 hours shown on the hour meter of the boat it came from. Because the motor reportedly operated at low RPM for most of its life, the 100-hour reading should be treated as a reference point rather than a guaranteed total engine-hour figure.

The engine has been compression tested at 120–125 PSI across the cylinders, providing valuable information about the consistency and condition of the engine.

The motor is supplied with controls, rigging, and propeller, making it a convenient ready-to-mount-and-run package without the need to source the basic components separately.

This Yamaha 90 HP offers a practical option for fishing boats, aluminum boats, utility boats, skiffs, and other vessels appropriately rated for 90 HP.

Engine Features at a Glance

• 90 HP Yamaha outboard
• 1999 model year
• 2-stroke engine
• 3-cylinder configuration
• Approximately 1,140 cc displacement
• Freshwater use only
• Used JDM engine
• Compression tested and inspected
• 120–125 PSI compression across cylinders
• Approximately 100 hours indicated on donor boat hour meter
• Hour reading provided as a reference, not a guaranteed total
• Controls included
• Rigging included
• Propeller included
• Complete ready-to-mount-and-run package

Yamaha Outboard Technical Specifications

Specification	Details
Brand	Yamaha
Model	90 HP
Year	1999
Horsepower	90 HP
Engine Type	2-Stroke
Cylinder Configuration	3-Cylinder Inline
Displacement	Approximately 1,140 cc
Bore × Stroke	82 × 72 mm
Full-Throttle RPM	Approximately 4,500–5,500 RPM
Fuel System	Carbureted
Ignition	CDI
Starting System	Electric Start
Control System	Remote
Lubrication	Oil Injection
Cooling	Water Cooled
Gear Ratio	Approximately 2.00:1
Hours	Approximately 100 indicated*
Compression	120–125 PSI across cylinders
Condition	Used – Inspected

*The approximately 100-hour reading comes from the donor boat’s hour meter and is provided as a reference only. It is not represented as a guaranteed total engine-hour figure.

Outboard Features and Equipment

Proven Yamaha 90 HP Performance

The Yamaha 90 HP two-stroke platform provides a strong combination of power, simplicity, and practical performance for fishing and recreational applications.

Compression Tested

Compression readings of 120–125 PSI across the cylinders provide buyers with useful information about engine condition and cylinder consistency.

Freshwater-Only History

The engine reportedly spent its life in freshwater only, an important part of its history when evaluating a used marine engine.

Complete Rigging Package

Controls, rigging, and propeller are included, helping simplify the repower process.

Electric Start

Electric starting provides convenient operation from the helm when properly installed and connected.

Oil Injection

The Yamaha platform uses an oil-injection lubrication system, eliminating the need for conventional manual premixing when the system is functioning correctly.

Performance and Repower Benefits

• Reliable 90 HP Yamaha power
• Proven 2-stroke design
• Freshwater-only history
• Compression tested at 120–125 PSI
• Consistent compression across cylinders
• Approximately 100 hours indicated by donor boat hour meter
• Controls included
• Rigging included
• Propeller included
• Ready-to-mount-and-run package
• Excellent value for a budget-conscious repower

Performance & Applications

The Yamaha 90 HP is a versatile power range for a variety of fishing, recreational, and utility boats.

Potential applications include:

• Fishing boats
• Aluminum fishing boats
• Center-console boats
• Bay boats
• Utility boats
• Skiffs
• Flats and coastal fishing boats
• Small-to-medium recreational boats
• Repower projects

Always confirm the boat manufacturer’s maximum horsepower rating and required transom configuration before installation.

Compatible Boat Types

This Yamaha 90 HP can be suitable for appropriately rated:

• Fishing boats
• Aluminum boats
• Center-console boats
• Bay boats
• Utility boats
• Coastal fishing boats
• Recreational runabouts
• Other boats designed for approximately 90 HP

Actual compatibility depends on the boat’s maximum rated horsepower, transom height, steering system, controls, mounting configuration, and intended use.

Engine Condition and Service History

Used JDM – Compression Tested & Inspected

The engine is being sold as a used Yamaha outboard with a freshwater-only history.

The listing reports:

• Approximately 100 hours shown on the donor boat’s hour meter
• Low-RPM operation for much of its reported service life
• 120–125 PSI compression across cylinders
• Freshwater use only
• Controls included
• Rigging included
• Propeller included

The stated hour reading should be considered a reference rather than a guaranteed engine-hour total.

For an older used outboard, buyers should still verify starting, cooling-water flow, charging output, gear shifting, lower-unit condition, fuel-system operation, and overall running condition before installation whenever possible.

Included Equipment

This listing includes a complete package with:

• Yamaha 90 HP 2-Stroke Outboard
• Controls
• Rigging
• Propeller
• Standard engine components supplied with the motor
• Ready-to-mount-and-run package

Customer Pickup

Important Before Purchase

Because this is a 1999 used two-stroke outboard, buyers should verify:

• Boat maximum horsepower rating
• Required transom height
• Steering compatibility
• Control compatibility
• Wiring and harness requirements
• Propeller specifications
• Lower-unit condition
• Cooling-system operation
• Charging-system output
• Fuel-system condition
• Compression results
• Exact items included with the package

About The Hour Reading

The donor boat’s hour meter reportedly showed approximately 100 hours, but the listing notes that the motor operated at low RPM for most of its life.

Therefore, the 100-hour figure is presented as a reference point and not a guaranteed total engine-hour figure.

The strongest condition information supplied for this listing is the 120–125 PSI compression test across the cylinders, together with the reported freshwater history and inspection.

Frequently Asked Questions

1. Is this Yamaha 90 HP a 2-stroke?

Yes. This is a 1999 Yamaha 90 HP 2-Stroke outboard.

2. What are the compression readings?

The engine tested at 120–125 PSI across the cylinders.

3. Does the engine include controls and rigging?

Yes. Controls, rigging, and the propeller are included, providing a complete ready-to-mount-and-run package.

4. Is the 100-hour reading guaranteed?

No. The approximately 100-hour reading comes from the donor boat’s hour meter and should be treated as a reference rather than a guaranteed total engine-hour figure.

Order Your Yamaha Outboard from Machinery Store

Confirm your boat’s horsepower rating, transom height, steering and rigging compatibility before installation. Contact Machinery Store to confirm availability, the exact package contents, delivery charges and any applicable warranty terms.