Another thread on here got me looking at the power curves of my Yanmar
4JH3-HTE, which I always thought of as producing 100 horsepower @ 3800RPM, or somewhat less continuous at 3700RPM.
To my surprise I noticed that the crankshaft power output curve, and the similar shaft output curve, told a different story, with peak power of more than 100 hp and at lower RPM
. The rated power of the engine
power curve, which goes straight up to 100hp at redline.
The curves diverge greatly. At 2200 RPM
, the propellor power is less than 20 horsepower, while 50 are being generated at the shaft. Shaft and propellor power converge at redline.
Anybody have any clue what all this means?