B3.9 and B5.9 Series Engines
About the Manual
Section i - Introduction
About the Manual
This B3.9 and B5.9 Series Engines Troubleshooting and Repair Manual is intended to aid in determining the cause
of engine-related problems and to provide recommended repair procedures. The manual is divided into sections by
system. Each section provides general information, specifications, diagrams, and service tools, where applicable. The
How to Use the Manual
This manual is organized to provide an easy flow from problem identification to problem correction. A list of trouble-
shooting symptoms containing the most common engine problems is in the Troubleshooting Symptoms, Section TS.
This manual is designed to use the Troubleshooting Symptoms as a guide in locating the problem and directing the
end user to the correct procedure for making the necessary repairs to the engine. Complete the following steps to locate
and correct any problems:
1. Locate the symptom on the Section Contents page of Section TS.
2. Reference to the page number where the Troubleshooting Symptom Tree is found is made to the right of the
symptom tree title.
3. The left column of boxes in the Troubleshooting Symptom Charts indicates a probable cause of the problem, starting
at the top with the simplest and easiest to repair, and continuing downward to the most difficult.
4. The right column of boxes provides a brief description of the corrective action with a reference number to the correct
procedure used to make the repair.
5. Locate the probable cause in the left column; then turn to the procedure referenced in the right column.
The Troubleshooting Symptom Charts are based on the following assumptions:
The engine has been installed according to the OEM's specifications.
The easiest repairs are done first.
"Generic" solutions are provided for most common OEM applications.
Refer to Section V for specifications recommended by Cummins Engine Company, Inc. for the engine. Specifications
and torque values for each engine system are given in Section V.