Basic Information Identification Make: Polaris Model: 400 Model Variant: ATV (All-Terrain Vehicle) Production Years Covered: 1985, 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995 Introduction Market Position Market Segment: Utility ATV Target Audience: Recreational riders, farmers, hunters, and early utility ATV users Competitive Analysis Competitors: Yamaha Moto-4, Honda FourTrax, Suzuki QuadRunner Key Features Key Features: Robust construction, reliable powerplant, capable off-road performance for its era Manual Details Coverage Areas Manual Type: Workshop Service Manual Language: English Format: PDF Download Primary Use: Mechanics and advanced DIY enthusiasts Manual Coverage Systems Covered Engine: Complete engine overhaul, tuning, carburetor, ignition system, cooling system, exhaust system Drivetrain: Transmission, clutch, drive shafts, differentials, chain/belt drive systems Suspension: Front and rear suspension components, shock absorbers, control arms, bearings Brakes: Brake system inspection, hydraulic lines, calipers, brake pads/shoes, master cylinder, bleeding procedures Electrical: Wiring diagrams, lighting, battery, charging system, starter, ignition switch, switches and controls Fuel System: Fuel tank, fuel lines, fuel pump, carburetor (if applicable), fuel filter Frame Chassis: Frame inspection, welds, mounting points, steering system components Bodywork: Body panels, fenders, seat, handlebars, plastics, trim components Procedures Included Maintenance: Scheduled maintenance checks, lubrication, fluid changes, filter replacements, belt/chain adjustments Repair: Step-by-step repair instructions for all major components and systems Troubleshooting: Diagnostic procedures for common and uncommon issues, fault codes interpretation (if applicable) Overhaul: Complete disassembly and reassembly procedures for engine, transmission, and other major assemblies Adjustments: Carburetor tuning, valve clearance adjustments, brake adjustments, clutch adjustments Specifications: Torque specifications, clearances, fluid capacities, timing settings Technical Depth Depth: Comprehensive, covering all aspects from basic maintenance to full engine rebuilds Manual Specifications File Format File Type: PDF Searchability: Likely text-searchable for quick information retrieval Printability: Printable pages for on-site use Resolution: High-resolution images and diagrams Print Quality Quality: High-quality digital reproduction of original factory documentation Binding Type Binding: N/A (Digital PDF) Paper Type Paper: N/A (Digital PDF) Engine Specifications Primary Engine Engine Type: 2-stroke, single-cylinder, liquid-cooled (common for many Polaris models of this era, though air-cooled variants may exist) Engine Displacement: Approximately 244cc - 350cc (specific to exact 400 model variant, manual should clarify) Bore X Stroke: Variable by specific model, manual will detail Compression Ratio: Variable by specific model, manual will detail Performance Horsepower Est: Typically 20-30 HP (estimated for the era and displacement) Torque Est: Good low-end torque for utility work (specific values in manual) Fuel System Fuel Delivery: Carburetor (e.g., Mikuni VM series) Fuel Type: Unleaded gasoline (refer to manual for octane rating) Oil Mixing: Premix for 2-stroke engines, or separate oil injection system (manual will specify) Transmission Standard Transmission Type: Automatic (CVT - Continuously Variable Transmission) with chain drive to rear axle is common for Polaris ATVs of this era. Drive System: 2WD (Rear-wheel drive) Optional Optional Drive: Some models may have had selectable 4WD options, manual will confirm Features Gear Reduction: High and low gear ranges typically included in CVT Transmission Fluid: Specific ATF or CVT fluid type (manual will specify) Dimensions Exterior Length: Varies by model, consult manual Width: Varies by model, consult manual Height: Varies by model, consult manual Weights Dry Weight: Typically 400-500 lbs (manual will provide exact figure) Payload Capacity: Significant for utility tasks (manual will specify) Towing Capacity: Likely in the 500-1000 lb range (manual will specify) Safety Features Ratings Safety Standards: Designed to meet relevant safety standards for ATVs of its era; specific ratings not typically applicable like cars. Active Features Active Safety: Responsive braking system, stable chassis design Passive Features Passive Safety: Handlebar grips, comfortable seating position for rider control Technology Features Infotainment Infotainment System: None (basic utility vehicle) Driver Assistance Driver Assistance: None Connectivity Connectivity Features: None Maintenance Service Intervals Oil Change Engine: Recommended every 50-100 operating hours or annually (manual specific) Spark Plug Replacement: Recommended every 100-200 operating hours or annually (manual specific) Air Filter Cleaning: Frequent checks, cleaning/replacement based on operating conditions (manual specific) Chain Lubrication: Frequent lubrication and tension adjustment, especially in dusty conditions (manual specific) Fluid Specifications Engine Oil: Specific 2-stroke oil blend or type recommended (manual essential for correct mix ratio/type) Coolant: Ethylene glycol based coolant (manual for specific type and mixture) Brake Fluid: DOT 3 or DOT 4 hydraulic fluid (manual will specify) Known Issues Common Wear Items: Brake pads/shoes, drive belts (CVT), suspension bushings, carburetor jets, ignition coils Potential Issues: Carburetor clogging due to fuel varnish, CDI unit failures, cooling system leaks in liquid-cooled models. Technical Specifications Spark Plug Gap: Specific gap provided in manual (e.g., 0.024-0.028 inches) Valve Clearance: Not applicable for 2-stroke engines unless a specific 4-stroke variant exists; if so, specs in manual. Tire Pressure: Recommended PSI for front and rear tires (manual specific, typically 5-7 PSI for ATVs) Vehicle History Brand Heritage Polarise Heritage: Polaris has a long history in powersports, initially known for snowmobiles before expanding significantly into ATVs and other recreational...