Segment:
Entry-level to mid-range utility ATV, known for its reliability and ease of use in recreational and light work applications.
Competitors:
Competed with models such as the Honda FourTrax 300/350, Suzuki QuadRunner 300/350, and Kawasaki Bayou 300/300.
Feature 1:
Durable and reliable 348cc air-cooled engine.
Feature 2:
Comfortable and stable chassis for its class.
Feature 3:
Automatic transmission for ease of operation.
Feature 4:
Shaft drive for low maintenance.
Value:
Provides essential information for maintaining and repairing the Wolverine across a wide range of years, saving owners significant costs compared to dealer service.
Applicable Years:
2003, 2004, 2005, 2006, 2007, 2008, 2009
Coverage Scope:
Comprehensive service, repair, and maintenance for the Yamaha Wolverine 350/400 4x2 ATV.
Estimated Page Count:
Typically 300-500 pages for a comprehensive factory service manual covering this range of model years.
Type:
Factory Service Manual / Workshop Manual
Engine Mechanical:
Complete engine overhaul, including cylinder head, piston, crankshaft, camshaft, valve train, lubrication system, and cooling system.
Fuel System:
Carburetor disassembly, cleaning, adjustment, and troubleshooting; fuel pump and lines; fuel tank and filter.
Ignition System:
CDI unit, ignition coil, spark plug specifications, timing, and troubleshooting.
Transmission Drivetrain:
Automatic transmission (likely Ultramatic or similar CVT variant for this era), clutch operation, gearbox, drive shafts, differential (if applicable), and wheel hubs.
Brakes:
Hydraulic brake system (front and rear), brake caliper servicing, master cylinder, brake lines, pads, rotors, and bleeding procedures.
Suspension Steering:
Front and rear suspension components (shocks, springs, A-arms), steering system (handlebar, tie rods, steering shaft), wheel alignment.
Electrical System:
Wiring diagrams, battery maintenance, charging system (stator, regulator/rectifier), starter motor, lighting (headlights, taillights, indicators), switches, and fuses.
Cooling System:
Air cooling system maintenance, fin cleaning, and general inspection.
Chassis Frame:
Frame inspection, body panel removal and installation, seat, fenders, and luggage racks.
Routine Maintenance:
Oil changes, filter replacements, spark plug service, air filter cleaning/replacement, chain adjustment (if applicable), lubrication points.
Troubleshooting:
Diagnostic procedures for common and uncommon issues, symptom-based troubleshooting guides.
Repair Procedures:
Step-by-step instructions for component disassembly, inspection, repair, and reassembly.
Specifications Data:
Torque specifications, clearances, fluid capacities, electrical resistance values, and performance data.
Wiring Diagrams:
Detailed electrical schematics for all systems.
Torque Charts:
Comprehensive torque value tables for critical fasteners.
Depth:
Factory-level detail, suitable for professional mechanics and experienced DIY enthusiasts. Covers complete overhauls and complex repairs.
Engine Type:
Single-cylinder, 4-stroke, SOHC, air-cooled
Bore X Stroke:
Specifications vary slightly by year; typically around 83mm x 64.5mm
Compression Ratio:
Typically around 8.6:1
Horsepower:
Estimated 20-22 HP (varies by year and tuning)
Torque:
Estimated 20-22 lb-ft (varies by year)
Carburetor:
Mikuni BS30 (or similar 30mm constant velocity carburetor)
Fuel Type:
Unleaded gasoline, minimum 87 octane
Fuel Tank Capacity:
Approximately 3.2 gallons (12 liters)
Ignition Timing:
Detailed in manual, typically fixed or adjustable via CDI unit.
Transmission Type:
Automatic (CVT - Continuously Variable Transmission) with forward, neutral, and reverse.
Drive System:
Shaft drive to rear wheels.
Final Drive Ratio:
Specifications vary by year, detailed in manual.
Clutch Type:
Automatic centrifugal clutch.
Transmission Fluid Type:
Yamaha's recommended gear oil or a suitable ATV-specific transmission fluid. Consult manual for exact specifications (e.g., SAE 10W-30 or 20W-40).
Engine Oil Change:
Every 1000 km or 6 months, whichever comes first (refer to manual for exact hours/miles).
Air Filter Cleaning:
Inspect every 500 km, clean or replace as needed. More frequent cleaning in dusty conditions.
Spark Plug Service:
Inspect and clean/gap every 1000 km or 6 months.
Brake Fluid Change:
Recommended every 2 years or as per manual inspection.
Valve Clearance Adjustment:
Typically every 2000 km or annually. Critical for engine performance and longevity.
Engine Oil Type:
Yamalube 4 (or equivalent) SAE 10W-30 or 20W-40 API SE, SF, SG type motor oil. Consult manual for specific viscosity recommendations based on temperature range.
Engine Oil Capacity:
Approx. 1.90 liters (2.0 US qt) without filter change, 2.10 liters (2.2 US qt) with filter change.
Brake Fluid Type:
DOT 3 or DOT 4 hydraulic brake fluid.
Common Issue 1:
Carburetor gumming/clogging due to fuel sitting, requiring cleaning and potential rebuilding.
Common Issue 2:
Wear on CV joints and boots due to off-road use and age.
Common Issue 3:
Slightly underpowered compared to some contemporary competitors, but reliable.
Common Issue 4:
Rear axle seal leaks, particularly after high mileage or hard use.
Yamaha Atv History:
Yamaha has been a pioneer in the ATV market since the introduction of the Tri-Moto in the early 1980s, consistently innovating with models like the Big Bear, Warrior, and Banshee. The Wolverine lineage builds on this legacy of robust and reliable off-road vehicles.
Wolverine Lineage:
The Wolverine 350/400 (often sharing the same chassis and engine architecture with minor updates across years) was a popular choice for riders seeking a balance of utility and trail performance. It evolved from earlier Yamaha 300-class ATVs, incorporating features that improved comfort and capability.
Production Period:
The Wolverine 350/400 platform was produced for a significant period, with this manual covering a substantial portion of its run from 2003 to 2009.
Manufacturing Location:
Yamaha's ATV manufacturing is primarily based in Japan and the United States.