1987 Honda Fourtrax 350 4x4 Service Manual

The 1987 Honda Fourtrax 350 4x4 is a rugged all-terrain vehicle featuring four-wheel drive capability, a reliable 350cc four-stroke engine, shaft drive system, independent front suspension, and durable construction. This service manual covers maintenance procedures, troubleshooting, specifications, and repair instructions for optimal performance and longevity. Below are key sections for maintenance schedules, engine service, transmission, electrical systems, and troubleshooting.

1. General Information 2. Maintenance Schedule 3. Engine Service 4. Transmission & Drive System 5. Electrical System 6. Brakes & Suspension 7. Fuel System 8. Cooling System 9. Troubleshooting 10. Specifications 11. Wiring Diagrams

General Information

Overview of the 1987 Honda Fourtrax 350 4x4 ATV including model identification, safety precautions, and tool requirements.

ComponentDescription
Model CodeTRX350 4x4
Engine Type4-stroke, OHC, air-cooled
Displacement350cc
Drive SystemShaft drive with selectable 4WD
Starting SystemElectric and auxiliary recoil
Fuel Capacity3.7 gallons (14 liters)
Dry Weight474 lbs (215 kg)
Front SuspensionIndependent double wishbone
Rear SuspensionSwingarm with dual shocks
BrakesDrum front and rear

Maintenance Schedule

Regular maintenance intervals for optimal performance and safety.

  1. Engine Oil Change: Every 100 hours or 6 months
  2. Oil Filter Replacement: Every 200 hours or 12 months
  3. Air Filter Cleaning: Every 50 hours or 3 months
  4. Spark Plug Inspection: Every 100 hours or 6 months
  5. Drive Shaft Lubrication: Every 200 hours or 12 months
  6. Brake Adjustment: Every 100 hours or 6 months
  7. Wheel Bearing Inspection: Every 200 hours or 12 months

WARNING! Always perform maintenance on level ground with engine off and cool. Use proper safety equipment.

Engine Service

Detailed procedures for engine maintenance and repair.

  1. Oil Change: Drain plug located bottom of crankcase, refill with 10W-40 motorcycle oil
  2. Valve Clearance Adjustment: Intake 0.15mm, Exhaust 0.20mm
  3. Spark Plug Replacement: NGK DR8ES-L, gap 0.028-0.031 inch
  4. Compression Test: Normal range 142-199 psi
  5. Carburetor Adjustment: Pilot screw 2-1/8 turns out from lightly seated

CAUTION! Engine must be cool before servicing. Torque cylinder head bolts to 20 ft-lbs.

Transmission & Drive System

Electrical System

Complete electrical system specifications and service procedures.

Battery: 12V 14Ah, charging voltage 14.0-15.0V at 5000 RPM

Charging System: AC magneto with rectifier/regulator

Ignition System: CDI electronic ignition

Headlight: 12V 30/30W halogen

Fuses: Main 20A, Sub 10A

Starter: 12V 0.9kW electric starter

Brakes & Suspension

Brake system maintenance and suspension adjustment procedures.

  1. Front Brake Adjustment: Turn adjuster on brake lever
  2. Rear Brake Adjustment: Turn adjuster on brake pedal linkage
  3. Brake Pad Replacement: Minimum thickness 1.5mm
  4. Front Suspension: Preload adjustable 5 positions
  5. Rear Suspension: Spring preload adjustable
  6. Wheel Alignment: Toe-in 0-10mm

Tip: Check brake fluid level regularly and replace every 2 years.

Fuel System

Carburetor service and fuel system maintenance.

  1. Carburetor Type: Keihin PD62A
  2. Main Jet: #122
  3. Slow Jet: #38
  4. Float Height: 18.5mm
  5. Fuel Filter: Replace every 200 hours
  6. Fuel Pump: Vacuum operated diaphragm type
  7. Throttle Cable: Free play 10-20mm

WARNING! Work in well-ventilated area. No smoking near fuel system components.

Cooling System

Air cooling system maintenance and overheating prevention.

Troubleshooting

SymptomPossible CauseCorrective Action
Engine won't startFuel, spark, compressionCheck fuel flow, spark plug, compression
Poor performanceClogged air filter, carb issuesClean air filter, inspect carburetor
4WD not engagingLinkage, differentialCheck shift linkage, front differential
Electrical failureBattery, fuses, wiringTest battery, check fuses, inspect wiring
OverheatingDirty fins, lean mixtureClean cooling fins, check carburetion

Reset: Disconnect battery for 30 seconds to reset electrical system.

Specifications

Wiring Diagrams

Complete electrical wiring schematics for the 1987 Honda Fourtrax 350 4x4 including color codes and connector locations.

Color Codes: R=Red, B=Black, W=White, G=Green, Y=Yellow, Br=Brown, Lg=Light Green

Main Harness: Runs from battery compartment to handlebar controls

Ground Points: Engine case, frame near battery

Service: Contact authorized Honda dealer for technical support

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