Vehicle Starting and Driving
S-11
3. Tachograph working order
Indications on tachometer scale:
a.
Green zone – operating range of maximum
performance
b.
Yellow zone –
c.
Red zone – engine overspeed range (risk of
immediate engine damage)
Always observe tachometer while driving the
vehicle.
Whenever possible keep engine running within
the economical range.
On downgrade, select an adequate gearbox
speed and monitor vehicle speed to avoid
engine operating in the danger range (red zone).
When the exhaust-brake is operating on down grades, select an adequate gearbox speed to keep engine
speed within efficient exhaust-brake operation
（
yellow
）
.
Always avoid engine over revving (red zone), as engine operation in this speed range can end up in
immediate engine damage or seriously jeopardize its durability.
The yellow range with red reticle can be used occasionally when the exhaust-brake needs to be used at its
efficiency limit, however, at risk of engine durability. Therefore, do not operate in this range in a normal
or usual way.
Summary of Contents for XMQ6900J series
Page 116: ...Common trouble and elimination C 16 Fault symptom Possible cause Eliminating method speed...
Page 128: ...Appendix A 4 Air braking schematic diagram...
Page 129: ...Appendix A 4 Electric schematic diagram of the complete vehicle 1...
Page 130: ...Appendix A 4 Electric schematic diagram of the complete vehicle 2...
Page 131: ...Appendix A 4 Electric schematic diagram of the complete vehicle 3...
Page 132: ...Appendix A 4 Electric schematic diagram of the complete vehicle 4...
