A diesel engine fails to start, even though it can be barred over, but not cranked over. The probable cause is __________.
• Difference between "barred over" manually and "cranked over" on starting air or electric starter • What a seized piston or bad bearing would feel like when you try to turn the engine by hand • How an air start system works and what happens if air cannot get to the starting motor or starting valves
• If the engine can be turned by hand with a bar, what does that tell you about the internal mechanical condition of pistons and bearings? • Which of the listed problems would completely prevent the starter from being able to rotate the engine, even though it is free to turn mechanically? • Which option is most directly related to the starting system rather than the internal engine condition?
• Confirm that "seized" or badly fitted internal parts usually make the engine hard or impossible to bar over • Think about whether insufficient compression would stop the crankshaft from rotating, or just make it fail to fire • Consider how a closed/blocked starting air line or valve would affect the starter’s ability to turn the engine, even if the engine itself turns freely by hand
No comments yet
Be the first to share your thoughts!