How do you avoid overloading mechanical engines?

What EGT's are your C18's running at 80% load? The 1200HP V8 MAN's run EGT's right around 1250F at 80% load in 83F water.

Mine are not that high. I usually run about 72-75 % load and the EGTs are around 900 if memory serves.

Thanks, was curious. The man v10-1100 CR's also run at 1250F at 80% load, both boats will hit 2350-2360 rpms WOT with full fuel/water.

Really? Of the multitude of reasons there could be for higher EGT you think it’s safe to assume that higher load could be the only causative factor?
I think I am done here. Your superior intellect and unmatched experience will have to carry the day.
Good Day, Sir.

Those EGT numbers match what I recall seeing from the same motors, the EGT numbers from the MMDS are taken before the turbo. Using the aviation EGT gauges with the thermocouple in the exhaust riser directly downstream of the turbo, in the mid 800’s, closer to the numbers @DOCKMASTER is reporting.

I think you mean MMDS are taken after the turbo but before the aftercooler.

@mapism that you would characterize this exchange as a “debate” speaks volumes. Something you might want to think about when you are pondering your resolutions for the New Year.
Good Day!

Let's just say that what was a pleasant conversation, with exchange of ideas and information, has been turned into a debate. And I don't come here for a debate.

https://bfy.tw/Q0Vp

Mapism, English is my mother language, and your use of the word "debate" is appropriate. It appears that CaptPKilbride thinks of a debate as a very heated discussion with yelling and shouting and name-calling. I was on the debate team in high school, and our debates were very polite, as you have been in this thread. You are not the one who was out of line here. I look forward to many more of your "debates." You have lots of useful information.

Always the diplomat,huh?

So the MAN's take EGT's before the turbo. I wasn't aware of that. Thank you for the correction and photo's.

I remember replacing one of those EGT senders at the end of the exhaust log.
Kept logging intermittent exhaust gas temp alarms.
Took a first guess which one it was and rotated between the engines.
Problem moved with the sender. Dam thing is expensive.

Load %, at any given rpm is defined as the actual power demand (=power output) / maximum power available. Electronic engines infer actual power output from fuel consumption. Electronic engines do the math, but even with mechanicals, one can determine load % by knowing fuel consumption and referencing a chart.

More importantly, EGT peaks at max horsepower, but most engines reach max horsepower at a lower rpm than max rated rpm. The reason EGT drops is that fuel consumption PER REVOLUTION drops after max hp rpm, so the heat of combustion, per rpm also drops, but the volume of air that is absorbing that heat remains constant per rpm.