To Marvin Pierce 671 Engine Performance Graph

"Marv, after reading a number

"Marv, after reading a number of issues and of course your responses, I believe that you are the resident expert on Detroit Diesels. Being new to the world of diesels, I have a pair of 671-Ns in my 43 Viking. I have a engine performance graph from Johnson & Towers for fuel consumption. My confusion is which of the two lines to look at. The top line states "FUEL CONSUMPTION" and the line below states "PROPELLER LOAD - FUEL CONSUMPTION". They both come together at 2500 RPMs showing about 16.5 gal/hr. Which line should I look at when I am trying to estimate fuel burn. Also, if you don't mind, could you explain the difference between the two.

Thanks For Your Help
(Trying to Learn)

Bob"

you want to read the propller

you want to read the propller load the rated shaft horsepower is what the engine is rated at.

"Marv, thanks for your help.

"Marv, thanks for your help.

Bob"