1986 Kenworth W900 Manual

The 1986 Kenworth W900 is a classic conventional truck model featuring a long-nose design, robust construction, and versatile powertrain options. This manual covers operation, maintenance, specifications, and troubleshooting for the W900 series manufactured in 1986. Below are key sections for safety, features, operation, maintenance, specifications, and troubleshooting.

1. Features at a Glance 2. Pre-Operation Inspection 3. Operating Procedures 4. Specifications 5. Controls and Instrument Panel 6. Maintenance Schedule 7. Engine and Powertrain 8. Electrical System 9. Brake System 10. Regulatory Information 11. Troubleshooting

Features at a Glance

Key components: Conventional long-nose design, aluminum cab construction, various engine options, air-ride suspension, comprehensive instrument panel.

Feature	Description
Cab Design	Aluminum construction with aerodynamic improvements
Engine Options	Cummins, Caterpillar, and Detroit Diesel engines available
Transmission	Manual transmissions ranging from 9 to 18 speeds
Suspension	Air-ride cab and optional air-ride suspension
Brake System	Air brakes with anti-lock capability
Instrument Panel	Comprehensive gauges and warning lights
Electrical System	12-volt system with circuit breakers
Fuel System	Dual fuel tanks with capacity up to 300 gallons
Cooling System	Heavy-duty radiator with engine protection
Cab Comfort	Air conditioning, heating, and sleeper options

Pre-Operation Inspection

Complete daily inspection before operation.

Walk-around inspection: Check tires, lights, and visible damage.
Fluid levels: Engine oil, coolant, brake fluid, power steering.
Air system: Check for leaks and proper pressure buildup.
Brake test: Verify parking and service brake operation.
Electrical check: Test all lights and warning systems.

WARNING! Never operate vehicle with brake system warnings or low air pressure. Ensure all inspections are completed daily.

Operating Procedures

Follow proper starting, driving, and shutdown procedures.

Starting: Depress clutch, ensure neutral, turn key to start position.
Gear selection: Use proper shifting technique for manual transmission.
Braking: Apply service brakes gradually; use engine brake when available.
Shutdown: Allow engine to idle briefly before turning off.
Parking: Apply parking brake and chock wheels when necessary.

CAUTION! Always use seatbelt. Never operate with low oil pressure or high temperature warnings.

Specifications

Wheelbase: Various configurations from 180 to 280 inches
Engine Options: Cummins NTC-350, Caterpillar 3406, Detroit Diesel 8V92
Horsepower: 350 to 450 HP depending on engine
Transmission: Fuller RT-12509, RT-12513, or similar 9-18 speed manuals
Front Axle: 12,000 to 20,000 lb capacity
Rear Axle: 38,000 to 65,000 lb capacity
Brakes: Air-actuated S-cam brakes with ABS
Fuel Capacity: 150 to 300 gallons total
GVWR: Up to 80,000 lbs depending on configuration

Controls and Instrument Panel

Main controls: Steering wheel, gear shift, clutch, brake and accelerator pedals.

Instrument Panel: Speedometer, tachometer, oil pressure, coolant temperature, voltmeter, air pressure gauges, fuel level, warning lights for brakes, engine, and electrical system.

Secondary controls: Headlight switch, wiper controls, heater/AC controls, engine brake switch, hazard lights, trailer brake control.

Maintenance Schedule

Regular maintenance ensures optimal performance and longevity.

Daily: Check fluid levels, tire pressure, air system, lights
Weekly: Inspect brakes, suspension, steering components
Monthly: Check wheel bearings, universal joints, exhaust system
Every 15,000 miles: Change engine oil and filters
Every 30,000 miles: Service transmission and differentials
Every 100,000 miles: Major engine service and component inspection

Tip: Keep detailed maintenance records for warranty and resale value.

Engine and Powertrain

Various diesel engine options with manual transmissions.

Engine operation: Monitor gauges for normal operating ranges
Cooling system: Maintain proper coolant level and mixture
Fuel system: Use clean diesel fuel; drain water separators regularly
Transmission: Use proper shifting technique; avoid gear grinding
Clutch: Adjust free play; avoid riding clutch
Driveline: Check U-joints and carrier bearing regularly

WARNING! Never operate engine with low oil pressure or overheating. Shut down immediately if warnings occur.

Electrical System

12-volt system with alternator, batteries, and comprehensive circuit protection.

Brake System

Air brake system with automatic slack adjusters and anti-lock capability.

CAUTION! Test brakes daily. Never operate with air pressure below 60 PSI. Park on level surface with wheels chocked when necessary.

Regulatory Information

FMVSS compliance: Meets all applicable Federal Motor Vehicle Safety Standards. EPA emissions standards compliant for 1986 model year. Copyright © 1986 Kenworth Truck Company; all rights reserved. For support, contact authorized Kenworth dealerships or Kenworth Customer Service.

Troubleshooting

Symptom	Possible Cause	Corrective Action
Engine won't start	Battery, fuel, or starter issues	Check battery voltage; ensure fuel flow; inspect starter circuit
Low power	Fuel filter, air filter, turbocharger	Replace fuel and air filters; check turbo operation
Brake issues	Air leaks, worn linings	Check for air leaks; inspect brake linings and drums
Electrical problems	Alternator, batteries, connections	Test alternator output; check battery connections
Transmission noise	Low oil, bearing wear	Check transmission oil level; inspect for internal damage

Service: Contact authorized Kenworth dealership for major repairs and warranty service.