Thread: Your next boat?
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Old 04-14-2012, 01:09 PM   #19
FF
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Really? Perhaps someone should tell Grand Banks as they and the original company, American Marine, have been doing exactly this with staggering success on a worldwide basis since 1966

No question , the REASON for the "staggering success"is very simple ,
the engines installed, Ford Econo-Power marinizations or Perkins which have an remarkably high rated power compared to their actual output capability.

No one in their right mind would consider using a tractor or taxi or light truck engine suitable for a constant rated load.

Like your car , it might say 455hp on the air cleaner , but in an earth mover it wouldn't last the day. In your car 200,000+ miles .

Same with tractor or lawn implement takeouts . FAB! for an hour or two on the pin, followed by weeks of plodding at 3 GPH.

A real industrial engine IS useful at 100% load factor , DD's and others do it for tens of thousands of hours in the oil patch hooked to big pumps.24/7/365

For lower noise and good service life , most pleasure boat assemblers use engines that are comfortable at about 75% power , or less.

Genset builders prefer 80% load at 90% RPM, again for longer service life.

Single or twin if 70 hp moves the boat , 135 rated making 70 great , 5 gph and not too much noise , with 2 engines is only 40hp each , not great but still at 3 gph ,not that all that far from what they were built for.

The method of success was engine selection , of an engine with great low power ability to run almost forever.

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