mjm yachts 50z Downeast, Руководство пользователя

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CHAPTER 5
5.3
Racor Filters for each of the engines plus the
genset are your first line of defense against bad
fuel and are installed on the aft face of the
forward engine room bulkhead.
Check
these filters regularly for any
accumulation of water or contamination. Water
will appear as a dirty gray, cloudy substance in
the clear bowl. You should be able to see thru
the pink fuel in the bowl at all times. Also,
you should not see bubbles passing through
the filter while running. This would indicate a
leak on the suction side of the fuel system.
FILTER ACCESS LID – Be sure to close fuel
shut-off valve before opening. Be careful to
seal properly without pinching gasket.
CLEAR GLASS INSPECTION BOWL
WATER DRAIN PETCOCK – If water seen
in bowl, hold a paper cup under the petcock
and drain until clear fuel seen.
5.4 FUEL CONSUMPTION
You can learn some things from the MJM fuel efficiency chart on the next page.
It’s the Horsepower Applied. Assuming similar hull designs, fuel efficiency is a function of HP
applied to overcome resistance. You can see there is very little difference in fuel efficiency
between the twin IPS 600 and the triple IPS 600. Lighter, narrower boats are easier to push
through the water and are more efficient.
Range of Efficient Operation It’s interesting to note that it doesn’t particularly matter whether
you are going 19 knots or 30 knots on a 50z, nautical miles per gallon remain fairly constant.
Cruising Speed
Volvo Penta suggest that given suitable conditions, 200 RPM below wide
open throttle, or about 3250 RPM, producing a 30 knots on the twin IPS 600 and 35 knots on
the triple IPS 600. is a high cruise speed.
RACOR PRIMARY FUEL FILTERS (4)
FUEL SYSTEM