Originally Posted by Tspringer
Chief... no added stuff. In fact, we removed a giant engine driven refrigeration compressor
during my refit
replacing it with a DC powered frigoboat keel-cooled system.
I did have the alternator bearings and brushes replaced and it is a Balmar 100 amp model but its the same alternator we have used all along. The alternator is the only thing other than water pump the belt turns.
I'm no diesel mechanic, so normally I'd stay out of this, but man, I really feel you pain. Given that you've not found the problem, maybe a fresh approach and some basic analytics can help, so let me take a cut at this:
First, some things we know (or at least believe to be true):
1) The engine sat unused for over six months during rework.
2) Components (turbo, ext) were removed for a clean-up.
3) Two problems appeared when engine was put back into service (fuel in oil
and black smoke in exhaust).
4) New pump seems to have fixed fuel
5) There are two injector models, didn't see that correct nozzles for your engine/pressure has been confirmed.
6) Diver indicates prop & shaft are clear.
7) You claim that nothing was added to the engine to increase load, BUT you did remove a refrigeration compressor and replace it with a DC-powered frigo-boat system.
8) Alternator bearings & brushes were replaced.
Now, some suggestions, based upon my review of of the entire thread (I try to give credit where due, and I *think* I got the post numbers right - apologies in advance for errors). This might not be worth more than you're paying for them, but might help spur some lateral thinking:
Suggestion #1: As someone pointed out (in post #110) "if engine is overloaded there must be some other drag on it". I went through the entire thread looking for clues and anomalies, and the only thing that made my hair stand on end that nobody seems to be commenting on is the fact that you pulled a compressor from the engine and converted to a DC-powered frigoboat unit, which seems like a fairly substantive change in configuration.
Agreed, pulling the compressor would presumably reduce drag, but then you added a corresponding load to the alternator (plus also a hull-mounted cooler, which adds drag to the hull
?). Are you sure that all these changes aren't putting extra load on the engine? Coupled with other changes (the 2000lb added weight, maybe the injector nozzle issue?) could this be your problem? If the frigoboat unit is drawing a significant amount of current
during your engine tests it might be loading things more than you think.
Can you shut it off, maybe pull the alternator belt or otherwise verify that all this isn't loading your engine up? Just a thought as it does stand out as a rather significant configuration change.
Suggestion #2: You state (in post #21) that you're sure the engine is now using clean fuel
, but I didn't see anything about draining and replacing the fuel. Are you assuming the new filter guarantees good fuel? It did sit for quite a long time, and the injectors were quite fouled when the problem appeared. Could this been something as simple as a problem of stale fuel ?
Suggestion #3: Someone called out the fact (in In post #61) that there are two models of injector for this engine, with differing fuel pressure settings - are you sure you had the right injector nozzles for your model? If you had the injectors for the non-turbo engine I would assume the problem would be not enough fuel, not too much, but it's an unanswered question. I'd confirm this before abandoning the engine!
Suggestion # 4: Someone suggested (in post #71?) that the added 2000lb of weight could be the problem, coupled perhaps with a marginal prop pitch? Someone suggested that you dump your fresh water and try again. This seems a stretch on its face, but coupled with other factors (bad injector nozzle setting, other potential loads on the engine?) you could have passed a threshold, so you might consider going even further and perhaps drain fuel & offload anything heavy/movable and trying another run. Oh, and if you've been doing these trials with a full crew, consider trying with just one or two aboard. None of this would require a haul-out, so it seems to be worth a shot...
Okay, again I'm no diesel expert, but thought this could serve as a level-set for those who are. Good luck, and really hope you nail this soon...