Yanmar 3gm30f blue exhaust smoke

BCC Forum
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I have a yanmar 3gm30f engine on my sailboat, I recently replaced the timing cover gasket. After a couple weeks of running the engine oil started leaking from the shims on the high pressure fuel pump. I might have damaged them during the timing cover gasket replacement. I tried to seal them with loctite 243 but it leaks worse. Also now there is heavy blue smoke coming out from the exhaust when I run the engine, I am aware that the blue smoke is because it is burning excessive oil. I am in the process of replacing the shims with new ones, but I have no where the oil is getting in to the fuel. By the way I replaced the lift fuel pump (on the starboard side of the engine) and the diaphragm is not broken.
Any ideas regarding where the oil is leaking into the fuel?

Thank you,

Oz

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OK … The basics. Diesels need four fluids,

  • Air (OK, actually a gas)
  • Lubricating oil
  • Coolant or water,
  • Diesel fuel (made from oil)

Here is how they combine

  • Air and Lubricating Oil => Blue Smoke
  • Air and Coolant => White Smoke or steam
  • Air and too much Diesel fuel => Black Smoke or Soot from incomplete combustion

I’m hearing you are ask - Why all the “blue smoke”?

The engine is running => good,
Too much smoke => not good.
Blue smoke => engine is burning lubricating oil.

How is lubricating oil getting into the combustion chambers? Usually wear, blow-by from stuck rings, bad valve seals, that sort of thing - need more information to go further.

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Thank you Vixen,
I have resolved the problem. I had replaced the Fuel injection pump shims coating them with loctite 423 which increased the thickness and messed up the timing and created the blue exhaust smoke. I have replaced them with new ones (they come pre coated) and that fixed the problem.
Oz