Cylinder cut out test locked out

[Rob Baker]

I have a head scratcher issue here. Qsc 8.3 has a miss at rpm above 1200. Had Cummins diagnose with insite program but cylinder cut out test is locked out. No explanation on why. Engine at temp but no good.
Cummins tested ECM and brought up to date with latest cals. Still nothing.

Engineering analyzed raw data and found instability in rail pressure realitive for ECM requests. Changed pressure actuator and engine became smoother but produced white smoke with throttle transition. Each time the rpm bumped up white smoke puff then clean burning.

Cummins mounted multipul flashes in an attempt to get cut out test to run. No good.

Under load the engine now lacks power, gobbling fule 23.8 gph at 2200 rpm. Normal would be less than 14 gph. Cloud’s of white smoke resulted.

Cummins appeared stumped as to why and suggesting ECM is corrupted.

Filters are fresh, prop and bottom clean. Engine has 1085 hrs and has been well maintained.

Any advise is very welcome. Been chasing this ghost for months.

Topic

[Tony Athens]

Single or twin engine boat?

If twin and the other engine runs good, then start swapping things. ECM 1st.

If not, then you do not have much of choice that to decide what to start with–ECM, injectors, another NEW Fuel actuator ( we have seen a 50% ++ failure rate on the last 10 new engines start-ups engine lately). Researching this after really getting pissed off turned up that this goes back a few years. Some bad batches out there.

If the on-board tech using Insite could not sort it out, then you are not in good shape–Have you talked with his “boss”?

[Author]

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