G
Guest
Guest
Can anyone tell me the fuel consumption of a Evenrude 70hp accross a range of rpm\knots?
Geoffs
Active member
The answer is - It All Depends!
Not very helpful, but as a rough guide you can reckon that a two stroke outboard will use about 1 gallon per hour per 10 hp developed. So your 70hp will use something like 7 gals per hr at full chat.
Again very roughly, at lower revs the power developed will follow a propellor law, ie square law. So if max engine revs for 70hp is 5,000rpm, half revs, 2,500rpm fuel consumption will be a quarter, say 2 gph.
How all this relates to knots depend size of boat, hull shape / type to name just a couple of factors.
How close the set up gets to square law, ie power of 2 depends on various things, such as propellor. My own 19ft sterndrive V hull comes in at about 1.8, as best as I can measure.
Old Chinese proverb 'Man who sail boat into rice field, soon get into paddy'
Not very helpful, but as a rough guide you can reckon that a two stroke outboard will use about 1 gallon per hour per 10 hp developed. So your 70hp will use something like 7 gals per hr at full chat.
Again very roughly, at lower revs the power developed will follow a propellor law, ie square law. So if max engine revs for 70hp is 5,000rpm, half revs, 2,500rpm fuel consumption will be a quarter, say 2 gph.
How all this relates to knots depend size of boat, hull shape / type to name just a couple of factors.
How close the set up gets to square law, ie power of 2 depends on various things, such as propellor. My own 19ft sterndrive V hull comes in at about 1.8, as best as I can measure.
Old Chinese proverb 'Man who sail boat into rice field, soon get into paddy'