We have a 5424 in our sailboat. we're kind of far from home right now, in panama. two days ago on our way here the engine started bogging down and cutting out. First I changed my Racor fuel filter and drained and refilled the bulb, the problems persisited. Then I changed the fuel filter on the engine and bled the air from the system, the engine ran for 5 to 10 minutes then bogged down and cutting out again. I re-bled the system, and it started again, and I ran the throttle up high. The speed of the engine fluctuated, going from the set throttle speed, bogging down then coming back up. This went on for a few minutes before it bogged down and cut out again. Any ideas about what could cause this? Air in the injectors? Bad injectors, how do I crack and bleed them out?