Diesel Engine Start Question??

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Bilge Dweller
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Diesel Engine Start Question??

Post by Duckman »

I passed my written test then i came to the orals and got stumped on this Question.
Your deisel engine will not start , It is ONLY a fuel related problem.
What would it be?

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D Winsor
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Post by D Winsor »

There are a number of "Fuel" related problems that will stop a diesel engine from starting There may be more but these should give you the idea.
1) Mechanical Over Speed tripped or other shut down parameter activated
2) Plugged Fuel Filter
3) Fuel Valve to engine shut
4) Air in Injection Lines
5) High fuel Back Pressure (Return Line Plugged)
6) Fuel Temperature Too Hot (Vapour Locking of injectors & fuel Pumps)
7) Engine Jacket Water temperature too low. (Engine unable to generate enough heat of compression to fire while cranking)
8) Engine not timed correctly
9) Failed Governor
10) Sticking or Jammed Fuel Rack
11) Failed Injection Pump Cam shaft Drive
12) Failed Fuel Oil Booster Pump

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Engineering Mentor
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Currently located: Nova Scotia / Caribbean

One or two more ideas

Post by Dieseldame »

For fuel related issues it is also good to look at the fuel lines for blockages, on some Racors the entrance to the filter takes quite a turn and can be a spot for blockage (look at vacuum reading if equipped with the gauge).

Could also be water in the fuel.

my 2 cents

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The Dieselduck
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Dont forget the obvious stuff...

Post by The Dieselduck »

Do you have enough fuel in the day tank ? The right fuel; valves on; quick closing valves open? Booster pump running...

My two cents
Martin Leduc
Certified Marine Engineer and Webmaster
Martin's Marine Engineering Page

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Engineering Mentor
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Engine no start Chief

Post by conrod »

Its amazing, I come back from a month in Singapore and you guys have been busy eh.

Engine no start, fuel related. Well I must agree with you Martin. Start from basics and work your way there. Being a medium speed guy, but slow speed a long time ago, I would tend to start at the day tank as well, then the primary filters, then the fuel lever on the engine. A slight step back to check a feed pump, or booster.............all simple quick stuff.

Many years ago I had a 3/E come to me with similar problem. However it was not a fuel issue.........he forgot to open the air !!

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Leak Patrol
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Diesel Engine Start Question??

Post by carbob »

It was stated in one of the responses that the fuel may be too hot, but it could also be that it is too cold, as in the case of a slow speed engine not changed over to MDO. I worked on an older B&W KEF engine where the injectors had to be manually bled off until you had hot fuel prior to starting. The new MC type engines circulate internally, doing away with this practice. Also, it could be that your ouncture valves amy be stuck, not allowing the fuel pump to build up pressure.

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Post by lovevmc »

2) Plugged Fuel Filter


I used to meet such problem

Officer of the Watch
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Fuel problems

Post by Wyatt »

Many moons ago when I was much younger, I worked on a Canadian Deep Sea Vessel, the Western Hemlock. Yes, a Canadian crewed ship! Anyway, during a voyage one of the generators just shut down. The next one in line started up and went on load. This was all accomplished through the magic of those little black boxes, back then they were black and sealed. No working parts to be found. Anyway, I digress, the C/E happened to be in the E/R at the time and we both went to investigate why the engine decided to shut down. While we were examining this engine, the generator that was running shut down and our 3rd and last generator started and went on line. I can tell you that the urgency in finding out what was happening is becoming more apparent. We split the flange on the fuel supply line to the generator and discovered no fuel flowing. The header tank was full to bursting, so what gives. The C/E and I began following the line to the header tank, it meandered all over the engine room and then went under blown on insulation along a bulkhead. We began cutting the insulation off and continued following this line when we came across a bypass valve and then an in line strainer, all encompassed under a thick layer of blown insulation. As soon as we openned the bypass valve, fuel flowed.
I just thought I would post this funny story to let you know that things can be fixed by just being methodical, who would have thought a strainer would be insulated!!!!

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