Cummins NT855 Big Cam 3, 4 Engine Troubleshooting & Repair Manual

Covers: Cummins NT855 Big Cam III and Big Cam IV Engines

• Contact us with 8-digit ESN if you have compatibility questions

Pages: 693
Format: PDF
File size: 46mb
Works with: Windows/Mac/Tablet
Notes: Searchable, printable, instant download

This downloadable PDF manual provides instructions to troubleshoot and repair (including complete disassembly/assembly) the Cummins NT 855 “Big Cam” 3 or 4 engine.  Over 600 pages with clickable links and bookmarks in printable and searchable digital PDF format for your computer, tablet or smartphone.

PT pump/injector rebuild manuals sold separately.

Topics:

Introduction 

Engine Identification

• General Engine Specifications
• Engine Views

Troubleshooting 

• Procedures and Techniques
• Air Compressor Problems
• Alternator Malfunctioning
• Connecting Rod Bearing Noise
• Coolant in the Lubricating Oil
• Coolant Loss
• Coolant Temperature Above/Below Normal
• Engine Crankcase Gases (Blowby) – Excessive
• Engine Cranks, But Will Not Start (No Exhaust Smoke)
• Engine Decelerates Poorly
• Engine Hard to Start, or Will Not Start (Exhaust Smoke Present)
• Engine Power Output Low
• Engine Noise – Excessive
• Engine Runs Rough or Misfires In Operating Range (Warm Engine)
• Engine Starts But Will Not Keep Running
• Engine Surges
• Engine Surges While Operating at Rated RPM and Load
• Engine Vibration – Excessive
• Engine Will Not Crank or Cranks Slowly
• Engine Will Not Reach Rated Speed When Loaded
• Engine Will Not Shut Off
• Excessive White Smoke at Idle
• Exhaust Smoke Under Load – Excessive
• Fuel Consumption – Excessive
• Fuel in the Coolant
• Fuel in the Lubricating Oil
• Idle – Rough
• Low Power or Excessive Smoke (Low Turbocharger Boost Pressure)
• Lubricating Oil Consumption – Excessive
• Lubricating or Hydraulic Oil in the Coolant
• Oil Pressure High or Low
• Lubricating Oil Sludge in the Crankcase – Excessive
• Lubricating Oil Temperature Above Normal
• Main Bearing Noise
• Mechanical Variable Timing Will Not Switch to Advanced or Retarded Timing Mode
• Piston Noise
• Surge in Top Gear – Road Speed Governor Not Set Correctly
• Throttle Response Slow (Engine Dies Going Downhill)
• Turbocharger Leaks (Engine Oil or Fuel)
• Turbocharger Noise
• Variable Speed (VS) Governor Problems
• White Smoke – General Information
• Symptoms Cause and Correction Charts

Engine Systems Repair (including disassembly/assembly

• Cooling System
• Lubricating Oil System
• Combustion Air System
• Compressed Air System
• Fuel System
• Electrical System
• Base Engine Components

Engine Testing (In-Chassis)

• General Engine Test Specifications and Procedures
• Chassis Dynamometer Operation
• Engine Run-In Procedure

Engine – Remove and Install

Torque Values

Alphabetical Index