Yamaha 1990-95 250 HP Outboard Specs & Maintenance
Unleash true offshore power with the 1990–1995 250 HP V6 2-stroke outboard motor. Built on a massive 191 cu. in. (3130 cc) 76-degree V6 block, this legendary engine delivers raw torque and reliable performance for classic sportboats. Whether you’re restoring a vintage powerhouse or performing routine DIY service, explore our database for precise factory specifications and technical data to keep this two-stroke icon running at peak performance.
Complete Technical Specifications
| Specification | Details |
|---|---|
| Model / Horsepower | 250 |
| Year Range | 1990-95 |
| Engine Type | 76 LV 2-st |
| Cylinders | 6 |
| Displacement | 191 in (3130 cc) |
| Bore x Stroke | 3.54 x 3.23 in (90 x 82 mm) |
| Compression Ratio | 5.4:1 |
| Full Throttle RPM | 4500-5500 |
| Idle Speed (Neutral) RPM | 675-725 |
| Idle Speed (Trolling)RPM | 575-625 |
| Spark Plug (NGK) | BR8HS-10 |
| Spark Plug (Champion) | QL78C |
| Spark Plug Gap | 0.035-0.039 in (0.9-1.0 mm) |
| Ignition System | |
| Ignition Timing (Idle) | 4-8 ATDC |
| Ignition Timing (Carb Pickup) | 4-8 ATDC |
| Ignition Timing (Full Advance) | 16-20 |
| Fuel System | |
| Starting System | |
| Oil Injection System | |
| Injection Oil Ratio | Precision Blend |
| Gear Oil Capacity (mL/cc) | 1150 |
| Gear Oil Capacity (Oz) | 38.9 |
| Approximate Weight | 506-525 lbs (230-238 kg) |
| Battery CCA / Reserve | |
| Battery Reserve | |
| Tach Pole Setting | 12 |
| Test Propeller Part Number | — |
| Test Propeller New Engine RPM | — |
Maintenance Summary
Keeping this 250 HP two-stroke running strong requires clean fuel delivery and steady ignition. For peak performance, use NGK BR8HS-10 spark plugs gapped to 0.035–0.039 inches (0.9–1.0 mm). Regular plug changes and lower unit service will ensure maximum holeshot power and long-term reliability.
Disclaimer & Information Notice: Specifications, fuel ratios, and maintenance guidelines listed on VintageMotorSpecs.com are compiled for historical reference and educational purposes only. Always verify data against an official OEM service manual prior to ordering parts or executing repairs. VintageMotorSpecs.com assumes no liability for repair errors, equipment damage, or personal injury resulting from the use of this data.
Spot an error or discrepancy in these specs? Please contact us with your engine details so we can update our database.
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