Model Segment:
Trail/Utility snowmobile, popular for its balance of performance and reliability.
Competitors 1988:
Arctic Cat El Tigre, Ski-Doo Safari, Yamaha Phazer.
Engine Type:
Reliable fan-cooled twin-cylinder engine.
Suspension:
Typically featured a front leaf spring suspension and a rear torsional spring or slide rail suspension.
Accessibility:
Known for its user-friendly design and relatively easy maintenance.
Engine:
Complete engine overhaul, diagnosis, and repair procedures for the Polaris 400cc fan-cooled engine.
Fuel System:
Carburetor adjustment, cleaning, rebuilding, fuel pump service, and fuel line maintenance.
Ignition System:
CDI ignition system troubleshooting, component testing (coil, stator, spark plugs), and timing adjustments.
Clutch System:
Drive clutch (primary) and driven clutch (secondary) disassembly, cleaning, inspection, and servicing; clutch alignment procedures.
Drivetrain:
Chaincase inspection, lubrication, and chain tension adjustment; track and suspension system maintenance.
Braking System:
Hydraulic brake system maintenance, caliper service, pad replacement, and brake fluid specifications.
Electrical System:
Wiring diagrams, lighting system service, starter motor operation, and battery maintenance.
Cooling System:
Fan cooling system airflow optimization and component inspection.
Suspension Steering:
Front and rear suspension lubrication and adjustment; steering mechanism inspection and service.
Bodywork Chassis:
Hood and body panel removal/installation, seat maintenance, and chassis component inspection.
Maintenance:
Scheduled maintenance tasks, lubrication points, and routine checks.
Troubleshooting:
Diagnostic charts and symptom-based troubleshooting guides for common operational issues.
Repair:
Detailed step-by-step repair instructions for all major components and systems.
Rebuilds:
Comprehensive procedures for engine and clutch rebuilding.
Adjustments:
Carburetor, chaincase, and steering adjustments.
Depth:
Comprehensive coverage from basic preventative maintenance to in-depth engine and drivetrain overhauls.
Engine Type:
2-stroke, fan-cooled, reed-valve twin-cylinder
Displacement:
Approximately 398cc (exact bore/stroke may vary slightly based on specific sub-model).
Cooling Method:
Fan-cooled
Ignition:
CDI (Capacitor Discharge Ignition)
Horsepower Est:
Approx. 35-40 HP (varies with tuning and altitude)
Carburetion:
Typically twin Mikuni VM30SS or similar.
Fuel Type:
Leaded or Unleaded gasoline with appropriate 2-stroke oil mix (pre-mix or injection system).
Oil System:
Autolube oil injection system or pre-mix.
Type:
CVT (Continuously Variable Transmission) system with Polaris Variable Ratio Drive (VRD).
Optional Transmission:
N/A for this model
Drive Clutch:
Primary clutch with adjustable weights and spring for optimal RPM engagement.
Driven Clutch:
Secondary clutch with spring and roller/button system for belt engagement.
Gear Reduction:
Internal gear reduction within the chaincase for final drive.
Safety Standard:
Operates under general snowmobile safety guidelines of the era.
Braking:
Hydraulic disc brake system for reliable stopping power.
Throttle Control:
Thumb throttle with return spring.
Lighting:
Headlight and taillight for visibility.
Kill Switch:
Handlebar-mounted kill switch for engine shutdown.
Initial Break In:
Refer to the original owner's manual for specific break-in procedures (typically 5-10 hours of varied riding).
Spark Plug Replacement:
Inspect every 500 miles or annually; replace as needed based on condition (e.g., NGK BR9ES or equivalent).
Chaincase Oil Change:
Annually or every 1000 miles. Use Polaris Premium Gearcase Lube or equivalent GL-4 80W-90 gear oil.
Clutch Cleaning:
Inspect and clean primary and secondary clutches annually or as needed, especially if performance issues arise.
Suspension Lubrication:
Lubricate suspension pivot points and grease fittings annually or as per manual recommendations.
Engine Oil:
2-stroke engine oil. Use a reputable brand meeting API TC or JASO FD specifications. If using autolube, use a dedicated injector oil.
Brake Fluid:
DOT 3 or DOT 4 hydraulic brake fluid.
Coolant:
Not applicable (fan-cooled engine).
Clutch Wear:
Wear on clutch rollers, bushings, and belt can affect performance. Regular inspection and maintenance are crucial.
Carburetor Icing:
A common issue with carbureted engines in cold, humid conditions. May require jetting adjustments or carburetor heat kit.
Exhaust Spiders:
Exhaust stifling can occur; periodic cleaning of exhaust ports and muffler is recommended.
Track Tension:
Improper track tension can lead to premature wear of the track and drive components.
Polarissnowmobiles:
Polaris is a well-established American manufacturer with a long history in snowmobiles, founded in 1954.
Indy Lineage:
The Indy nameplate has been a cornerstone of Polaris' snowmobile offerings, known for sporty performance and trail riding.
1988 Context:
The 1988 Indy 400 was part of Polaris' effort to offer a capable, mid-range snowmobile that bridged the gap between entry-level and high-performance models.
Manufacturing Location:
Polaris snowmobiles are primarily manufactured in the United States.
