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Old 12-08-2011, 04:39 AM   #8
RickB
Scraping Paint
 
City: Fort Lauderdale
Vessel Model: CHB 48 Zodiac YL 4.2
Join Date: Oct 2007
Posts: 3,804
Re: Izuzu diesel engines

The engines used on that ship (Wartsila 46) are available as natural gas burner (Wartsila 50) but the engines on the Oasis are oil burners. The pure gas burners use a spark plug, the dual fuel versions use a shot of diesel to ignite the gas.

They are very sophisticated engines with an electronically controlled common rail injection system and the fuel quantity and timing can be tweeked for each cylinder. It isn't done by the watch engineer by turning a rheostat or something that simple but the manufacturer and the shoreside engineers can remap the engine control system remotely. Some of it is done automatically based on fuel quality and energy content.

Even old style mechanical engines are monitored to balance the power output of each cylinder and there are mechanical adjustments we can make to equalize things. We regularly take what are called "indicator readings" that create a chart of cyliner pressure relative to crank angle. Modern engines can display that on a computer screen in the control room. That is how they discovered there were problems on the Oasis. That kind of thing is routine maintenance.

Some versions of that engine use variable valve timing so if things got out of whack there, it could cause differences in compression but I don't think that version of engine is installed on Oasis. It is more likely that there were firing pressure differences but the TV producer chose to simplify the explanation.
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