Engine Diagrams; Problem Isolation And Correction - Dodge D250 1990 Service Manual

Troubleshooting Logic
Page 9A-2
Base Engine Components
DODGETurbo Diesel
Troubleshooting L o g i c
Engine Diagrams
A schematic of each of the major engine systems is provided at the beginning of the Section of the manual devoted
to troubleshooting and repairing that particular system.
The diagrams depict flow through the various engine systems. The information and configuration of the components
illustrated in the drawings are of a general nature.
Each Section also contains a discussion regarding diagnosing malfunctions for that specie system. A knowledge of
the systems can help you troubleshoot and repair the engine.
Problem Isolation and Correction
The following Troubleshooting logic is designed to heip you organize your study of a problem and plan a procedure
to correct it. The series of fault/logic charts given do not provide all the answers, but they should stimulate a train of
thought that will lead you to the source of the trouble.
Be sure to consider any maintenance or repair action that could have caused the problem.
If the engine surges or runs rough Initially after not being used for 2 months or more, do not assume that the engine
has a malfunction. Varnish can form on the internal parts of the injection pump and the oil film can drain from the
piston rings. Operate the engine for at least 5 minutes before troubleshooting.
The basic procedure is as follows:
• Study the problem thoroughly.
• Relate the symptoms to your knowledge of the engine components and systems.
- Double-check before beginning the disassembly.
- Solve the problem by deduction starting with the easiest things.
• Determine the cause of the problems and make a thorough repair.
- After making corrections, operate the engine in normal conditions to verify the cause of the problem was
corrected.