Wisdom

"The biggest satisfaction in life is to succeed doing something that others think you are not able to do so."

Friday, December 16, 2011

Main Engine Operating Troubles

In this article let us discuss the trouble shooting of the main engine when it turns on compressed air but receives no fuel charge to start

Operational Faults - Engine Receives No Fuel to Start .

In marine diesel engine which are mainly started by air ,the highly compressed air is used to start the engine when the engine picks up the speed the starting air is closed and fuel is injected then the engine start running in fuel this is the normal procedure .The engine which gets the starting air and when the engine picks up speed the fuel does not inject and so the engine does not fire .
So let us see what are the cases the engine receives no fuel :

Trouble shoot :Engine Turns on air but receives no fuel to start

1.Lube Oil or Jacket cooling water pressure is too low, but the control air is given to the starting valve but the hydraulic interlock closes the fuel supply .

2.Fuel lever is at a zero position , normally during starting the engine when engine gains the desired rpm the fuel lever is pulled and minimum amount of fuel is injected to starting .

3.Regulating linkage is jammed or blocked .

4.Return Springs are loose or defective regulating linkage does not move to a position releasing a fuel charge .

5.Governor is defective ,It does not release a fuel charge .The amount of fuel supply is decided by variable speed governor so the governor should be dis engaged if it is defective .

6.Starting lever blocking device is jammed and does not release control oil supply to the cut out servomotor.

7.The cut out servomotor ,or its control valve is jammed in cut out position.

8.The running direction interlock is uncoupled .

9.The rotary slide valve of running direction safety interlock is seized in at end position .

10.The automatic cut out device is defective .

11.The three way cock of the automatic cut out device are closed .

12.Control oil pipes are incorrectly connected.Normally after the overhaul of the main engine the control oil pipe wrongly connected .

13.Control oil pipes are obstructed or defective due to leaking .

14.The load indicator does not indicate a charge .The engine works normally and the fuel is injected correctly but the load indicator fitted may be defective shows the wrong reading .

No comments:

Post a Comment