(2)
Torque Wrench - 50 to 400 pound-inches
(3)
Oversize Wear Ring - METAL FORM, Kent, Wash., or JET PRODUCTS CORP., San Diego, Calif.
(4)
Ball Joint Bearing Nut Wrench
(a)
Perferred: F72999-( )
(b)
Optional: ST2580-153-( )
(5)
Pneumatic System Ball Joint Retainer Wrench - ST2580-163-( )
B. Remove Wear Ring (Fig. 201)
(1)
While holding retainer with retainer wrench unscrew bearing nut from retainer with bearing nut wrench.
(2)
Move nut away from joint and remove wear ring (if wear ring is solid, cut to enable removal).
(3)
Remove shims.
C. Install Wear Ring (Fig. 201)
(1) Install split wear ring in bearing nut and check that gap in split wear ring does not exceed
0.030 inch.
NOTE: Wear ring gap may be filed if necessary to facilitate installation in bearing nut but not to exceed 0.030-inch gap.
(2)
Assemble joint without shims and using ball joint and torque wrenches, tighten nut to 70-90 pound-inches torque.
(3)
Measure clearance between nut and retainer rim with feeler gage.
(4)
Record amount of clearance and add 0.012 to 0.014 inch to obtain total shim thickness.
(5)
Disassemble joint.
(6)
Apply coating of antiseize compound to threads of nut and retainer.
(7)
Reassemble joint using the combination of solid and laminated shims determined in step (4).
NOTE: Shims must not protrude beyond periphery of nut.
(8)
Hold retainer with retainer wrench and using bearing nut and torque wrenches, tighten nut to 380-400 pound-inches torque.
(9)
Check joint to ensure freedom of movement by hand.
(10)
Lockwire nut to retainer using two holes in nut closest to hole in retainer.
501
May 01/00 BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details. 36-19-21 Page 201
3. Ball Joint Leakage Test
A. General
(1) All ball joints will leak as design requirements in the assembly of the joint requires 0.005 clearance.
NOTE: Leakage from a cold ball joint will usually be greater than that of a warm joint. If leakage rate is questionable, establish a flow through the duct to obtain normal operating temperatures. If the leakage rate is acceptable during normal temperatures, no corrective action is required.
B. The following leakage definitions are based on duct pressures experienced when bleed air system is being pressurized with auxiliary power unit (APU). If engines are operating for check, engine power should be advanced as required to provide an equivalent duct pressure.
(1)
Diffused leakage.
(a) Air that is leaking around most of the circumference of the joint.
(2)
Concentrated air blast leakage.
(a) Leakage resulting from: flat area on the joint face, nick, burr, or deep scratch, damaged shims, or excessive wear ring end gap.
F89448
Duct Ball Joint 501
36-19-21Page 202 Figure 201 BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details. Feb 20/88
C. Check Ball Joint Leakage
(1)
Check that all air conditioning and pneumatic system circuit breakers are closed.
(2)
Check that L and R PACK switches are OFF.
(3)
Operate APU (Ref 49-11-0, APU Power Plant Operating Procedure) or run engine(s) (Ref 71-09-100, Power Plant (JT8D) - Operating Procedure).
(4)
Position engine BLEED switches and ISOLATION VALVE switch as required to pressurize ducts which include ball joint being checked.
(5)
Check for leakage at ball joint.
(a)
If diffused leakage is observed, check that fire warning and overheat detectors are not in leak area and that leakage cannot be felt on the hand approximately 12 inches from joint.
(b)
If jet blast (concentrated air blast) is observed, check that blast is away from any fire warning or overheat detectors and that air blast is not felt on the hand 12 inches from joint.
4. Ball Joint Approved Repairs
A. General
(1) Excessive leakage as identified in par. 3 may be eliminated by accomplishing the following repairs.
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