Service Manual

ISB, ISBe and QSB (Common Rail [...] Stall Speed Test
Section 5 - Fuel System - Group 05 Page 5-39
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Check the equipment manufacturer's specifications for the
time to stall or the acceleration time.
If the time is excessive, refer to the Stall Speed Checklist
at the end of this procedure.
Stall Speed Checklist
Yes No
1. The tachometer is in error.
2. Engine temperature is up to
or above 70°C [160°F].
3. The converter oil is up to
temperature 80°C [180°F].
4. The stall has been held
long enough for the engine
to accelerate to full-power.
5. The match curve stall
speed was recorded
correctly.
6. The converter oil is to the
converter manufacturer's
recommendation (SAE 30
instead of SAE 10, for
instance).
7. The engine-driven
accessory power
requirements exceed 10
percent of the gross engine
power. Check for abnormal
accessory horsepower
losses such as hydraulic
pumps, large fans,
oversized compressors,
and so on. Either remove
the accessory or accurately
determine the power
requirement and adjust
accordingly.
8. The unit is operating at an
altitude high enough to
affect the engine's power.
9. The converter charging
pressure is correct.
10. The tailshaft governor is
interfering with and
preventing a full-throttle
opening. Disconnect the
tailshaft governor. Do not
exceed the manufacturer's
maximum output speed.