Question

Describe the action you would take and outline possible reasons for failure in both the following cases:

(a) The engine fails to turn on starting air.

(b) The engine turns on starting air but fails to fire.

Answer 1

(a) When the Engine Fails to Turn on Starting Air, Actions to Take:

Ensure the air bottle pressure is sufficient. If it's low, start the air compressor to fill the air bottles.
Check control air pressure. If it's too low, check for leaks in the control air line and rectify any issues.
Ensure all valves in the starting airline are open and set correctly to supply air to the engine.
Inspect the auto start valve for malfunctions. If faulty, troubleshoot or replace the valve.
Confirm that the turning gear is disengaged. If the interlock is activated or the limit switch malfunctions, rectify the fault.
If the start air distributor is wrongly adjusted, make the necessary adjustments as per the manufacturer's manual.
If the Pneumatic control valve malfunctions, overhaul or replace it as needed.
Investigate any safety interlocks (e.g., low lube oil pressure) that might be preventing the engine from turning. Rectify any faults found.
Check the Engine control switch and set it if incorrect.
If the auxiliary blower isn't running or is in manual mode, switch it to auto mode.
If the engine hasn’t reversed correctly, inspect and rectify the reversing mechanism.

Possible Reasons for Failure:

(b) When the Engine Turns on Starting Air but Fails to Fire, Actions to Take:

Inspect the puncture valve to ensure it is properly vented. Identify and rectify any issues.
Check the manoeuvring gear for correct adjustment. Adjust as necessary.
Inspect the governor for any faults. Troubleshoot and rectify according to the manual.
Ensure the fuel lever on the local manoeuvring stand is correctly adjusted. Make adjustments if needed.
Check the fuel filter for blockages. Clean or replace the filter if necessary.
Verify that fuel oil pressure is adequate and that the fuel line inlet valve is open. Troubleshoot the fuel pump if pressure is low.
Ensure the control air signal to the governor is not restricted and that it's set at the correct level. Rectify any issues.
Inspect the fuel pump and injectors for any faults. Overhaul and rectify as necessary.
Ensure the correct grade of fuel is being used at the proper temperature. Check the fuel purification system for water contamination.
Check for jamming or sticking in the fuel linkage. Lubricate and ease up as needed.

Possible Reasons for Failure:

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