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Engine Troubleshooting

Author: Basil Mosenthal

Basil Mosenthal leans on his experience in the Royal Navy and ocean sailing to give you expert advice on what to do when faced with common engine problems

 

To discover more about your engine read Cockpit Companion by Basil Mosenthal and Diesels Afloat by Pat Manley.

 

Common engine problems include:

Possible solution:

  • Low battery voltage (check voltmeter)

  • If starting battery is low try other battery, or both batteries in parallel (if switch is fitted)

  • Check starter cables are secured REALLY TIGHTLY to battery terminals

  • Check cable connections to start switch and starter motor

  •  

Engine turns, but does not start (Don’t run battery flat)

  • Check fuel valve open and enough fuel in the tank

  • Check engine stop valve is closed

  • May be air in fuel. Check for loos connections in fuel lines. Bleed the fuel system.

  • His drill may differ between engines. Read your Engine Manual – and try iy out in harbour (eg. when the filters are being changed)

  •  

As a general guide:

  • Slack off the bleed screw on top for fine filter.

  • Word hand priming lever on lift pump until fuel without bubbles flows from the bleed screw..

  • Tighten up this screw while still pumping. Try engine again. If no success.

  • Slacken high pressure line to one injector, turn over ejngine until fuel without bubbles flows. Re-tighten.

    • NB: If, while pumping, no fuel at all flows from bleed screw, clean out the pre-filter and fit new element. Bleed the fuel system again. Carry spare elements for both pre-filter (and fine filter) for emergencies. Learn how to fit them.

     

Engine Overheating

  • Indicated by temperature alarm (if fitted) or temperature guage. Steam may come from exhaust instead of water. Engine will run but will seize up if cooling is not restored.

  • Check raw water is open and strainer clear Inspect hoses for any major leak

  • Check cooland level in header tank ( take care!)

  • If cover plate of raw water pump is hot, the impeller needs replacing. 

  •  

Replacing raw water pump impeller (Make sure exact spare is carried)

  • Turn off raw water seacock

  • Unscrew cover plate on pump, use water-pump pliers to remove old impeller, and clear any debris and broken vanes found inside outlets and inlets

  • Insert new impeller ( grease vanes well first). The vanes will set themselves in the right direction when the pump is switched on.

  • Please new seal carefully and replace the cover

  • Turn on raw water at seacock.


Article taken from Cockpit Companion by Basil Mosenthal
Copyright 2008 John Wiley & Sons