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BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
e) Make sure that the retainer ring is fully installed all around the groove in the retainer nut.
NOTE: The clearance between the ends of the retainer
____ ring will be 0.10 inch (0.254 mm) when it is correctly installed.
f) Examine the hub flange for installed counter-weights (See Figure 503). g) Examine each counterweight for the letters "TB" marked on the inner diameter face. h) Make a record of the part number and tang location of all counterweights.
NOTE: After the fan is indexed, the tang at the
____ 12 o'clock position is the No. 1 tang. The tangs are numbered 1 through 19 in the clockwise direction.
5) Make a record of their weight (PBS class number) and
location (tang number). 6) Remove all of the counterweights on the fan. 7) Install the inlet cone (AMM 72-31-01/401). 8) Do a Check Run with the steps given later in this
procedure.
(i) If counterweights are not installed, do these steps:
1) Install counterweights No. 1 (CW1) trial weights to the fan balance ring (See Table 503).
NOTE: Use assumed phase angle and sensitivity data to
____ find the CW1 trial weight location.
2) Remove the inlet cone (AMM 72-31-01/401). 3) Temporarily install the correction weights in the fan with
cotter pins. 4) Install the inlet cone (AMM 72-31-01/401). 5) Do a Check Run with the steps given later in this
procedure.
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BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
////////////////////////A / PW4000 SERIES /747-400 / ENGINES/MAINTENANCE MANUAL ////////////////////////
~............................................................................... | TABLE 503 | | TRIM BALANCE COUNTERWEIGHTS FOR THE FAN PLANE | ................................................................................. |CLS| CNTRWGHT PN 534493 |CNTRWGHT PN 534495 | CNTRWGHT PN 1B4294 | ................................................................................. | 1 |2.0 oz.in (1440 g.mm)|4.9 oz-in (3528 g.mm) | 12.8 oz-in (9216 g.mm) | ................................................................................. | 2 |2.4 oz.in (1728 g.mm)|5.3 oz-in (3816 g.mm) | | ................................................................................. | 3 |2.8 oz.in (2016 g.mm)|5.7 oz-in (4104 g.mm) | | ................................................................................. | 4 | |6.1 oz-in (4392 g.mm) | | ................................................................................. | 5 | |6.5 oz-in (4680 g.mm) | | 2...….....................…......................…..............................1
H. Check Run.
S 975-093-N00
(1)
Do a Check Run:
(a)
Thermally stabilize the engine with the steps given earlier in this task.
(b)
To do the trim balance survey, stop at the same N1 speeds used during the As-Is Trim Balance Survey and make a record of the data.
(c)
Do a slow decel (90-120 seconds) to IDLE.
NOTE: Trim balance data is only taken during the accel
____
vibration survey.
(d)
Operate the engine at IDLE for five minutes to let the engine become cool.
(e)
Use the Power Plant Operation (Normal) procedure to do the engine shutdown (AMM 71-00-00/201).
(f)
If the vibration levels are satisfactory, do these steps:
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