Oil & Fuel perkins ad3 152

[max kay]

HI I HAVE A AD3 152 3 CYLINDER PERKINS
my problem is that i have fitted it into a boat
the hours on the engine are 400
it starts first turn and runs sweet
temp is good
But i have a problem with it smoking really black not blue so i gather its fuel
so got the injectors re done it worked fine for one day then started the same thing again
so now the only thing i can think of is that the engine is not getting enough air
so before i go cutting more holes into the cover can any one give me some advice on this again it starts first turn and oil pressure is v-good
fuel filters have been changed and oil filters
i do need to add a bit of oil after running the engine for 18hours ie less than a point

 

[nspec]

Run it with the cover off or open before you make new holes. That way youll know if its an air problem. My money is that it is. Very common problem on a marine diesel application.