SailNet Community - View Single Post - fuel consumption gas vs diesel
View Single Post
post #19 of Old 09-12-2009
Courtney the Dancer
jrd22's Avatar
Join Date: Nov 2000
Location: San Juan Islands., WA, USA
Posts: 3,963
Thanks: 5
Thanked 30 Times in 29 Posts
Rep Power: 17
Negrini- I realize that I am not using all 62 hp when at 2500 rpm on an engine that will do 3500, but do the math, it still does not equate. Even if I were only using 40 hp to push Laurie Anne (40' - 24,000 disp.) by that formula I would be burning 2.2 gph which is over twice what in fact it uses. By this formula I should only be using 18 hp at cruise speed since I only use 1 gph. In fact, using that formula it is wrong for any of the scores of diesel engines I have owned and have paid for the fuel bills on, so I know how much they use. My current crab boat, for just one more example, has 200 hp, 190 at the prop, and I run it at 3400 rpm. WOT is 3800 and I average betweeen 6 -7 gph at that speed(I log every gallon that goes into it). According to this formula it should be burning close to 9 gph. The Volvo fuel consumption graph is close to my actual burn rate, a little higher. All I am saying is that this does not seem to be a reliable formula to use to estimate anticipated fuel consumption, and therefore required tankage.

SV Laurie Anne

1988 Brewer 40 Pilothouse

jrd22 is offline  
Quote Share with Facebook
For the best viewing experience please update your browser to Google Chrome