Pratt & Whitney Rzeszów S.A.
MAINTENANCE MANUAL
PZL-10W ENGINE
72-02-00
1997.07.15
Page 108
Export Control Classification: PL/UE 9E999
(4)
"Cold suspension" of the compressor turbine rotational speed N1 (no increase both N1
and compressor turbine outlet temperature (CTOT) after the engine light up).
(a)
Possible causes:
too low fuel pressure at the inlet to the fuel metering pump;
an air lock in the fuel control system;
a leak of the pipe line leading the air from the combustion chamber shield to the
fuel metering pump;
maladjustment or a malfunction of the fuel metering pump;
too early closing of the air bleed valves on the combustion chamber at extremely
low ambient temperatures.
(b)
Schematic procedure:
NOTE:
Before
taking
a
decision
to
change
the
fuel
metering
pump,
check
(acc.
to
75-32-00,
item
B) what kind are the air bleed valves on the combustion chamber.
If
necessary,
replace
the
valves
to
the
new
ones
(acc.
to
75-32-00,
REMOVAL/
INSTALLATION,
item
3)
or
adjust
the
valve
(acc.
to
75-32-00,
REMOVAL/
INSTALLATION,
item 4):
