" wrote in news:0bc6b40d-b372-405a-
:

First, it has now got an air leak in the
fuel system somewhere. I had to bleed the system at the injectors a
couple of times when the motor had sat for a few days (we did get some
sailing in). This is new, or at least new to the extent that
perceptible air is released when the injector is cracked.

Have the oil analyzed to look for fuel in the oil. If there's fuel in
the oil, the injection pump cylinders are leaking back oil past the
pistons into the crankcase of the engine as the engine oil also lubes the
injection pump crankcase. The injectors are higher than the pump, so
when the oil slides past the worn cylinders, air gets sucked in at the
nozzle and ends up in the injectors and injector lines you're bleeding to
get it to crank.

If there's no fuel in the crankcase, the injection pump has one or more
leaky fuel valves allowing fuel to back up back down towards the fuel
tank. Test this the next time you're going to leave the boat sitting for
a long period. Simply shut off the fuel tank valves as soon as you shut
down the engine, leave it all just sit for a few weeks, then see if air
bleeds out instead of fuel as soon as you crank. If air is STILL in the
injector lines, it'll also point you to problem A above, backing up into
the crankcase from the leaky pistons in the injectors because it can't
back up to the tank with the fuel valves all closed off. Pinch off the
return line with vice grips at the hose if there's no valve.

Air leaks are very interesting to find and correct....(c; But, if these
are the problem, it's not a fuel line air leak making the problem. Air
leaks don't occur sitting for days....fuel backup does.

Maybe that's what these guys are looking for in the crankcase....fuel
backup!
http://gcaptain.com/maritime/blog/th...-super-engine/
Air leaks there would be measured in cu ft....not bubbles in the
filter...(c;