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TROUBLESHOOTING
BY Service Manual
13-5
Engine Faults and Torque Limitations
Torque Reduction Chart Based on Intake Air Temperature
The intake air temperature will limit the torque at 3000 rpm if the air temperature is increasing.
Torque Limitation for Overheat
Protection
In the case of this limitation there are two possible
situations:
If an electronic fault occurs, it will be displayed on
the display-alarm and a P-Code is saved in the
system. These codes can be read with a diagnostic
tester. A substitute value (fixed value until fault
disappears) is activated (coolant temp=110,
fuel temp=90) and a torque reduction occurs. In this
case, the coolant temperature is also limited by the
torque limit which is described in
for Failed Sensors on page 13-3
value of the fuel temperature is fixed at 90°C and
that sets a limitation of approximately 75% from the
maximum torque
(Figure 13-1)
.
If the coolant temperature is over 108°C, an audible
alarm sounds and engine overheat is displayed on
the instrument panel display. At 120°C the torque
limitation is 30%
(Figure 13-2)
. If the fuel
temperature is too high (over 90°C) this limitation is
also active for the overheat prevention as shown in
Figure 13-1
. From 100 to 140°C the torque limit is
about 40% of the maximum torque. In this case
there is not an alarm on the instrument panel
display. In both cases, no P-Code appears.
Figure 13-1
Figure 13-2
Engine speed
2000 rpm
2000 rpm
Torque
Torque [N·m]
Intake air
temperature [°C]
Torque [N·m]
Intake air
temperature [°C]
Engine
4BY150
4BY180
100% (normal operation)
295
30-50
315
30-50
90%
265
60-90
285
60-90
80%
240
100-130
250
100-130
Engine
6BY220
6BY260
100% (normal operation)
450
30-50
450
30-50
90%
405
60-90
405
60-90
80%
360
100-130
360
100-130
Summary of Contents for 4BY
Page 1: ...BY series 4BY 6BY SERVICE MANUAL ...
Page 2: ...BY Service Manual BY series SERVICE MANUAL 4BY 6BY P N 0BBY0 G00100 MARINE ENGINES ...
Page 5: ...TABLE OF CONTENTS iv 4BY 6BY Service Manual This Page Intentionally Left Blank ...
Page 7: ...INTRODUCTION 1 2 BY Service Manual This Page Intentionally Left Blank ...
Page 21: ...SAFETY 2 14 BY Service Manual Safety Precautions This Page Intentionally Left Blank ...
Page 131: ...FUEL SYSTEM 6 2 BY Service Manual This Page Intentionally Left Blank ...
Page 159: ...FUEL SYSTEM 6 30 BY Service Manual Repair This Page Intentionally Left Blank ...
Page 161: ...COOLING SYSTEM 7 2 BY Service Manual This Page Intentionally Left Blank ...
Page 181: ...COOLING SYSTEM 7 22 BY Service Manual Repair This Page Intentionally Left Blank ...
Page 183: ...LUBRICATION 8 2 BY Service Manual This Page Intentionally Left Blank ...
Page 199: ...LUBRICATION 8 18 BY Service Manual Repair This Page Intentionally Left Blank ...
Page 201: ...TURBOCHARGER 9 2 BY Service Manual This Page Intentionally Left Blank ...
Page 211: ...TURBOCHARGER 9 12 BY Service Manual Repair This Page Intentionally Left Blank ...
Page 213: ...STARTER MOTOR 10 2 BY Service Manual This Page Intentionally Left Blank ...
Page 221: ...ALTERNATOR 11 2 BY Service Manual This Page Intentionally Left Blank ...
Page 261: ...ELECTRICAL AND ECU 12 34 BY Service Manual Repair This Page Intentionally Left Blank ...
Page 263: ...TROUBLESHOOTING 13 2 BY Service Manual This Page Intentionally Left Blank ...