(2)
Position fuel pump switches for applicable tank to ON. Check that low fuel pressure lights go out.
Note: If you must use the fuel boost pumps in the center tank, you must have a maintenance person or observer in the flight compartment to continuously monitor the LOW PRESSURE lights. Turn the applicable fuel boost pump to the OFF position if the LOW PRESSURE light for the center tank stays on.
(3)
Position hydraulic system B electrical pump 1 switch to ON. Check that low pressure light goes out.
(4)
Position hydraulic ground interconnect switch to OPEN.
(5)
Position bleed air isolation valve switch to OPEN.
(6)
Position applicable engine bleed air switch to ON. Check that pneumatic manifold pressure is greater than 30 Psig.
NOTE: If APU is to be used for pneumatic source during engine start, position APU bleed air switch to ON. Check that dual bleed light on P5 panel comes on.
(7)
Move engine start switch to GRD position and release.
NOTE: The engine start switch is held in the GRD position by a holding solenoid. When starter cutout speed is reached, the holding solenoid is de-energized and the start switch automatically returns to OFF position.
(8)
When N2 rpm reaches 15% (minimum) and N1 rotation is observed, move engine start lever to IDLE detent.
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CAUTION: WHENEVER, (1) THE ENGINE FAILS TO LIGHT WITHIN 20 SECONDS, (2) AN INDICATION OF Nl RPM IS NOT EVIDENT BY 20% N2 RPM, (3) A STARTING FUEL FLOW OF 1,100 LB/HR (500 KG/HR) OR MORE, OR (4) THE EGT IS CLIMBING RAPIDLY THROUGH 400°C DURING A START, RETURN THE START LEVER TO CUTOFF. CONTINUE TO MOTOR THE ENGINE FOR 10 TO 15 SECONDS TO REMOVE FUEL AND VAPOR OR EVIDENCE OF FIRE FROM WITHIN THE ENGINE, OR UNTIL EGT BECOMES NORMAL. AFTER SATISFACTORY CLEARING OF THE ENGINE, OVERRIDE THE ENGINE START SWITCH SOLENOID AND RETURN THE SWITCH TO OFF. IF STARTER IS DISENGAGED, DO NOT RE-ENGAGE STARTER WHILE REAR COMPRESSOR ROTOR IS ROTATING, IN ORDER TO EXTEND STARTER LIFE AND REDUCE CHANCE OF FAILURE OF STARTER SHEAR SECTION OR ENGINE DRIVESHAFT. AFTER ENGINE ROTATION CEASES, AND BEFORE ANOTHER START ATTEMPT, DETERMINE AND RECTIFY CAUSE OF THE UNSATISFACTORY START.
NOTE: To give improved hot section life, it is recommended that movement of the start lever out of the CUTOFF position be delayed until the engine has reached 20% N2 rpm, when possible. Ensure adequate duct pressure is available.
NOTE: The engine should light up within 20 seconds after start lever is moved to the IDLE detent. N2 rpm and EGT should be monitored immediately after light up to ascertain that engine accelerates normally and that EGT does not exceed limits specified in Engine Starting and Operating Limitations, Fig. 205.
NOTE: Following the above procedure during a developing hot start can usually prevent exceeding the temperature limits.
(9)
Check for starter cutout at 40% N2 rpm by observing a rise in pneumatic duct pressure and an audible starter solenoid valve actuation. On airplanes with start valve open light, check that light extinguishes. Check that start switch returns to OFF automatically at starter cutout. If using APU for starting, place APU bleed air switch or applicable engine bleed air switch in OFF position and check that dual bleed light goes out.
CAUTION: IF START VALVE LIGHT REMAINS ILLUMINATED, SHUT ENGINE DOWN IMMEDIATELY. CONTINUED ENGINE OPERATION WITH START VALVE LIGHT ILLUMINATED MAY RESULT IN DAMAGE DUE TO STARTER DISINTEGRATION. DO NOT EXCEED THE RECOMMENDED STARTER DUTY CYCLE.
(10)
If N2 has exceeded 40% and starter cutout has not occurred, manually return start switch to OFF and check for starter cutout by observing a rise in pneumatic duct pressure.
(11)
If pneumatic duct pressure does not indicate starter cutout even after manual switching, shut down engine, depressurize pneumatic duct, and correct malfunction before attempting restart.
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Feb 20/90 BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details. 71-09-100 Page 221
CAUTION: IF FUEL IS SHUT OFF BY INADVERTENT MOVEMENT OF THE START LEVER, DO NOT MOVE THE START LEVER IN AN ATTEMPT TO CONTINUE THE START. RETURN START LEVER TO CUTOFF AND THEN RETURN START SWITCH TO OFF. WAIT 30 SECONDS AFTER ENGINE HAS STOPPED ROTATING AND THEN MOTOR ENGINE FOR 20 SECONDS WITH THE START LEVER IN CUTOFF TO CLEAR ENGINE OF TRAPPED FUEL AND VAPORS. IF STARTER IS DISENGAGED, DO NOT RE-ENGAGE STARTER WHILE REAR COMPRESSOR ROTOR IS ROTATING, IN ORDER TO EXTEND STARTER LIFE AND REDUCE CHANCE OF FAILURE OF STARTER SHEAR SECTION OR ENGINE DRIVE SHAFT. OBSERVE STARTER LIMITATIONS. IF ENGINE START WAS ABORTED DUE TO HUNG START, CHECK POSITION OF TURBOFAN VALVE (Ref. 21-52-0) AND AIR CLEANER PURGE VALVE (Ref. 21-12-0). VALVES MUST BE IN CLOSED POSITION BEFORE ATTEMPTING ANOTHER START.
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