Operation Manual

Diesel fuel flow sensor kit Installation and Operation Manual
9
NAVMAN
A fuel consumption curve gives a picture of how
fuel consumption varies with engine RPM, and
allows you to select an economical cruising
speed for the given conditions. By plotting
fuel consumption curves for different boat and
weather conditions, you can understand how
fuel consumption, economy and range vary with
different conditions.
When you first get your Navman diesel flow
system installed on your boat, perform a test
run and plot a fuel consumption curve. For your
first test run, choose a calm day, with light wind
and little current; have a typical load aboard and
a freshly cleaned hull.
Then you can plot other fuel consumption
curves for different boat, weather or sea
conditions. Compare these with your first curve
to see how your boat’s performance changes
with conditions. These curves will be the
reference curves for your boat. As time goes by
you can refer back to this set of reference data
- you can plot another fuel consumption curve
under the same conditions and compare it to
the reference curve to check how your boat’s
performance is changing over time.
To plot a fuel consumption curve for given
conditions:
1 Take a series of readings of the fuel flows
and boat speed at different engine revs
and fill out the fuel consumption table
(see section 3-1)
2 Plot the data from the fuel consumption
table on a graph. Either photocopy the
graph on the next page or download a
copy from www.navman.com. On the one
graph, plot:
a Boat speed (column 5) against engine
RPM (column 1)
b Economy (column 6) against engine
RPM (column 1)
Section 3-2 shows a typical graph.
3 Interpret this curve to understand your
boat performance (see section 3-2).
3 Plotting a fuel consumption curve