Yamaha 1991 60 HP Outboard Specs & Maintenance
Looking to keep your 1991 60 HP 3-cylinder 2-stroke outboard running like new? This classic 52 cubic inch (849cc) inline powerhouse is a favorite among DIY marine mechanics for its impressive power-to-weight ratio and bulletproof reliability. Whether you are troubleshooting an ignition issue, performing routine seasonal service, or rebuilding the lower unit, our comprehensive technical database provides the exact factory specifications and maintenance specs you need to keep this vintage 2-stroke purring on the water.
Complete Technical Specifications
| Specification | Details |
|---|---|
| Model / Horsepower | 60 |
| Year Range | 1991 |
| Engine Type | IL 2-stroke |
| Cylinders | 3 |
| Displacement | 52 cu-in (849 cc) |
| Bore x Stroke | 2.83 x 2.74 in (72.0 x 69.5 mm) |
| Compression Ratio | 6.1:1 |
| Full Throttle RPM | 4500-5500 |
| Idle Speed (Neutral) RPM | 750-850 |
| Idle Speed (Trolling) RPM | 550-650 |
| Spark Plug (NGK) | B8HS-10 |
| Spark Plug (Champion) | L78C |
| Spark Plug Gap | 0.035-0.039 in (0.9-1.0 mm) |
| Ignition System | CDI Micro |
| Ignition Timing (Idle) | 6-8 ATDC |
| Ignition Timing (Carb Pickup) | 5-7 ATDC |
| Ignition Timing (Full Advance) | 21-23 |
| Fuel System | Carb |
| Starting System | Manual and/or Elec |
| Oil Injection System | PB or 50:1 PM |
| Injection Oil Ratio | PB or 50:1 PM |
| Gear Oil Capacity (mL/cc) | 610 |
| Gear Oil Capacity (Oz) | 20.6 |
| Approximate Weight | 203-247 lbs (92-112 kg) |
| Battery CCA / Reserve | 380 (70) |
| Battery Reserve | 124 minutes |
| Tach Pole Setting | 6 |
| Test Propeller Part Number | YB-1620 |
| Test Propeller New Engine RPM | 4950-5150 |
Maintenance Summary
Proper ignition service is vital for this 3-cylinder 52 cu. in. engine. Always run NGK B8HS-10 spark plugs gapped precisely between 0.035–0.039 inches (0.9–1.0 mm). Keep fuel fresh with proper 2-stroke oil mixing, check lower unit lube regularly, and inspect the water pump impeller annually to ensure optimal cooling.
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Notice: Specifications, fuel ratios, and maintenance guidelines listed on VintageMotorSpecs.com are compiled for historical reference and educational purposes only.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.
Non-Affiliation Notice: VintageMotorSpecs.com is an independent historical reference database and is not affiliated, associated, authorized, endorsed by, or in any way officially connected with Outboard Marine Corporation (OMC), Mercury Marine, Yamaha, Honda, or any of their subsidiaries or affiliates. All product names, trademarks, and registered trademarks are property of their respective owners.