The crankshaft of a diesel engine reaches the starting RPM, but fuel oil in cylinders does not ignite and the diesel engine stops.

28 Jul '19, 12:41

July 28, 2019, 12:41 p.m.
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From the symptoms one can judge a fuel insufficiency at the first place. Check the fuel supply: service tank, supply and circulating pumps, proper fuel oil line setup. If any maintenance was carried out o the fuel system and part of it was disassembled, the purging of air may be required. Prime the fuel system.

Fuel may be contaminated with water. Mixed with diesel oil, it prevents DO from firing. In case of residual fuel heated above the 100 deg C, the water contained in fuel evaporates and causes air locks in the fuel system.

In case of engine with puncture valves installed on fuel injection pumps, check that puncture valves are not activated or stuck in open position.

The next thing to check is operation of fuel injection pumps. Open the cam shaft covers and ensure that the fuel pump rollers follow cams smoothly and do no get stuck. At the same time check for signs of fuel oil leak from the injection pumps into the camshaft space. Defective pumps or rollers with pushrods to be overhauled, plungers and barrels replaced.

Check the delivery valve of fuel injection pumps. They may fail and pass the gasses from the combustion chamber back to the fuel system. This will create the gas pockets in the fuel system and make it operation unstable.

Check fuel injectors. Nozzle may get clogged due to the bad quality fuel or by cold fuel. The last may happen if engine, operating on residual fuel, or it’s FO system cooled down. Inspect and pressure test injectors, replace /overhaul faulty ones.

If engine pistons, piston rings and liners are worn to some extent or inlet/exhaust valves are leaking, the required compression pressure can not be reached in one or several cylinders. Check tightness of the combustion chambers of all units.

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28 Jul '19, 12:42

July 28, 2019, 12:42 p.m.
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