Market Position:
The Yamaha YFM 350 Wolverine was a popular recreational ATV in the late 1980s, known for its robust design and capable performance in various terrains. This manual targets owners and technicians looking to maintain and repair this specific model.
Competitive Analysis:
Competed with models from Honda (e.g., TRX 350), Suzuki (e.g., QuadRunner 4x4), and Kawasaki (e.g., Bayou 300). The Wolverine often stood out for its comfortable ride and utility features.
Key Features:
Designed for recreational trail riding and utility tasks. Introduced Yamaha's torque-converter automatic transmission on some variants, offering ease of use. Known for its durable chassis and reliable engine.
Coverage Areas:
General Information, Specifications, Periodic Checks and Adjustment, Engine, Cooling System, Carburetion, Drive Train, Chassis, Electrical, Troubleshooting
Page Count:
Not specified in product information, typically 200-400 pages for a comprehensive service manual.
Manual Type:
Service and Repair Manual
Software Requirements:
Adobe PDF Reader (or compatible PDF viewer)
Operating Systems:
All versions of Windows & Mac, Smartphones, Tablets
Interactive Features:
Zoom in/out functionality
Systems Covered:
Engine internal components (cylinder, piston, crankshaft, valves), Carburetor systems, Fuel delivery, Ignition system, Cooling system (radiator, fan, coolant flow), Transmission (gearbox, clutch), Drivetrain (drive shafts, differential if applicable, chain drive system), Suspension (front and rear), Steering system, Braking system (front and rear), Electrical system (wiring diagrams, lighting, battery, starting system), Frame and body components, Wheels and tires.
Procedures Included:
Routine maintenance checks and adjustments, Engine disassembly and reassembly, Carburetor cleaning and adjustment, Transmission service, Drivetrain inspection and repair, Suspension component replacement, Brake system bleeding and repair, Electrical system troubleshooting and repair, Diagnostic procedures for common faults, Recommended service intervals, Fluid specifications and capacities, Torque specifications for critical fasteners.
Technical Depth:
Comprehensive, covering both routine maintenance and in-depth repair procedures. Suitable for both experienced mechanics and DIY enthusiasts. Includes detailed step-by-step instructions, illustrations, and diagnostic flowcharts.
Troubleshooting Depth:
Detailed troubleshooting guides with symptoms, probable causes, and corrective actions for various mechanical and electrical issues. Includes diagnostic flowcharts.
Repair Procedures:
Step-by-step instructions for component removal, inspection, repair, and reinstallation. Includes critical torque values, clearances, and specifications.
Primary Engine:
348cc, Air-Cooled, 4-Stroke, SOHC, Single-Cylinder
Horsepower:
Approximately 20-22 HP (Est. for 1987 model)
Torque:
Approximately 20-22 lb-ft (Est. for 1987 model)
Fuel System:
Carburetor (likely a Mikuni BS34 or similar)
Bore X Stroke:
83.0 mm x 64.5 mm (Est.)
Compression Ratio:
9.2:1 (Est.)
Ignition System:
CDI (Capacitor Discharge Ignition)
Oil Capacity:
Approximately 2.0-2.5 Liters (with filter change). Specific capacity requires manual verification.
Spark Plug:
NGK DPR7EA-9 or equivalent (Requires manual verification for exact type and gap).
Standard Transmission:
Automatic (Yamaha's Ultramatic or Torque Converter Automatic Transmission)
Optional Transmission:
Not applicable for this model year; typically offered with the automatic transmission.
Features:
Continuously Variable Transmission (CVT) with high/low range and reverse on some variants. Smooth power delivery and ease of operation.
Transmission Fluid:
Yamalube (or equivalent API GL-4 Gear Oil).
Overall Length:
Approximately 72.0 inches (1829 mm)
Overall Width:
Approximately 42.0 inches (1067 mm)
Overall Height:
Approximately 43.0 inches (1092 mm)
Dry Weight:
Approximately 490 lbs (222 kg)
Ground Clearance:
Approximately 5.5 inches (140 mm)
Front Tire Size:
AT22x8-12 (Requires manual verification for specific ply rating)
Rear Tire Size:
AT22x10-10 (Requires manual verification for specific ply rating)
Wheel Bolt Pattern:
4x110mm (Typical for Yamaha ATVs of this era)
Ratings:
N/A (ATVs are not typically rated by NHTSA or IIHS in the same way as cars/trucks. Safety is primarily dictated by rider skill and adherence to manufacturer recommendations.)
Active Features:
Front and rear drum brakes (disc brakes may be present on some variants, manual verification needed). Neutral safety start.
Passive Features:
Full floorboards with heel guards, Thumb throttle with a safety trigger, Handlebar grips, Reflectors.
Service Intervals:
Initial service at 100-200 miles. Regular checks: oil change every 500-1000 miles or annually. Spark plug inspection/replacement: every 500-1000 miles. Air filter cleaning/replacement: every 200-500 miles or as needed. Chain lubrication and adjustment: every 100-200 miles. Brake system checks: every 500 miles. Full tune-up recommended annually. (Specific intervals require manual verification).
Engine Oil Type:
Yamalube 4 (or SAE 10W-30 API SG or higher engine oil).
Coolant Type:
Permanent type antifreeze (50/50 mixture with distilled water) (Requires manual verification).
Brake Fluid Type:
DOT 3 or DOT 4 Brake Fluid (Requires manual verification).
Known Issues:
Carburetor jetting and cleaning due to fuel varnish from infrequent use or ethanol-blended fuels. Wear on the automatic transmission belt and clutch components. Carburetor float bowl leaks. Ignition coil failure. Front suspension bushings and ball joint wear.
Oil Filter Part Number:
Yamaha 1UY-13440-00-00 or equivalent aftermarket (e.g., K&N KN-143).
Air Filter Part Number:
Yamaha 3JF-14451-00-00 or equivalent aftermarket (e.g., UNI UP-100).
Brand Heritage:
Yamaha has a long-standing history in powersports, dating back to its motorcycle origins. It entered the ATV market in the early 1980s and quickly established a reputation for innovation and quality.
Model Evolution:
The YFM 350 Wolverine was introduced as a successor to earlier Yamaha utility ATVs, offering a blend of utility and recreational capabilities. It paved the way for subsequent Wolverine models with more advanced features and engine options.
Production Years:
The YFM 350 Wolverine platform was produced from the mid-1980s into the early 1990s, with various updates and engine configurations.
Manufacturing Locations:
Primarily manufactured in Japan, with some assembly potentially occurring in other global locations.
Recognitions:
While specific awards for the 1987 YFM 350 Wolverine are not prominently documented, Yamaha ATVs of this era consistently received positive reviews for their reliability and performance in outdoor publications and by consumers.
Ratings:
Consumer satisfaction was generally high for Yamaha ATVs during this period due to their robust engineering.
Certifications:
N/A (Not applicable to vehicle certifications in the automotive sense.)
