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OPTIMUM USE OF TACHOGRAPH - CONTINUED

NOTE

It is not necessary to operate the engine at maximum rpm for

good performance. The engine performs efficiently at low

and middle speed ranges and offers a deﬁnite fuel advantage

at these reduced speeds. Control rpm by tailoring engine

speed to the load requirements and desired road speed.

1. Use tachometer hand (Figure 12, Item 3) of tachograph (Figure 12, Item 1) to

monitor engine rpm in all gear ranges. When manually downshifting transmission

while tractor is moving, monitor tachometer hand (Figure 12, Item 3) to ensure

maximum 2,100 rpm engine speed is not exceeded.

2. Control engine rpm through proper use of accelerator and gear selection for load

requirements and desired road speed. For the M915A1 in normal driving

situations, use gear range 1-5 and allow automatic transmission to control gear

selection and engine speed.

3. Use speedometer hand (Figure 12, Item 2) of tachograph (Figure 12, Item 1) to

monitor tractor ground speed in miles per hour (mph). Ground speed and engine

speed can be compared to help determine gear selection for any given condition

(WP 0005).

4. Use odometer (Figure 12, Item 5) on tachograph (Figure 12, Item 1) to record

distance traveled. Fuel consumption in miles per gallon (mpg) is calculated by

dividing the number of miles traveled by the number of gallons consumed.

5. Use clock hands (Figure 12, Item 4) on tachograph (Figure 12, Item 1) to estimate

destination time based on miles per hour (mph). For example, if traveling at a

ground speed of 60 mph, it will take one minute to travel one mile.

END OF TASK

Figure 12. Tachograph.

M915 THROUGH M920

M915A1

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0010

0010-15

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