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ALERT SERVICE BULLETIN
206-14-132
7 October 2014
MODEL AFFECTED:
206A/B and TH-67
SUBJECT:
FREEWHEEL
BLOCKAGE
HELICOPTERS AFFECTED:
Serial numbers 4 through 4690 and 5101 through
5313.
COMPLIANCE:
Part I - No later than 100 flight hours or
31 December 2014, whichever comes first.
ASSEMBLY
OIL
SUPPLY
Part II – 100 flight hours or 3 months, whichever
comes first, following the accomplishment of Part I of
this ASB.
Part III – Every 300 flight hours or 12 months,
whichever comes first, following completion of Part I
or Part II of this ASB.
DESCRIPTION:
Bell Helicopter Textron has received reports of helicopters with a blocked restrictor
located in the oil supply to the freewheel assembly. A restrictor blocked for an
undetermined period of operational time could cause the freewheel assembly to
malfunction. The restrictor(s) may become contaminated during maintenance which
may block the orifice. Part I of this bulletin requires that filter 50-075-1, restrictor 206040-254-001 or 206-040-244-001, and the hose and fittings between the transmission
and restrictor be removed, cleaned, inspected, and reinstalled. Part II of this bulletin
requires that for specific helicopters that have not incorporated TB 206-79-31,
installation of this filter is now required. Part III of this bulletin introduces a 300 flight
hour or 12 month, whichever comes first, recurring inspection and cleaning of filter 50075-1 and restrictor 206-040-254-001 or 206-040-244-001.
Applicability of this bulletin to any spare part shall be determined prior to its installation
on an affected helicopter.
ASB 206-14-132
Page 1 of 11
Approved for public release.
APPROVAL:
The engineering design aspects of this bulletin are Transport Canada Civil Aviation
(TCCA) approved.
CONTACT INFO:
For any questions regarding this bulletin, please contact:
Bell Helicopter Product Support Engineering - Light Helicopters
Tel: 450-437-2862 / 1-800-363-8023 / [email protected]
MANPOWER:
Approximately 3 man-hours are required to complete this bulletin. This estimate is
based on hands-on time, and may vary with personnel and facilities available.
WARRANTY:
There is no warranty credit applicable for parts or labor associated with this bulletin.
MATERIAL:
Required Material:
The following material is required for the accomplishment of this bulletin and may be
obtained through your Bell Helicopter Textron Supply Center.
Part Number
Nomenclature
AS3208-04
AS3208-04
AS3208-06
50-075-1
Packing
Packing
Packing
Filter
Qty
Note
1
4
1
1
1
2
3
Notes:
1. Applicable to helicopters S/N 4 through 253 and 914 through 4690.
2. Applicable to helicopters S/N 254 through 913.
3. Required if the filter is not installed or if TB 206-79-36 has not been incorporated.
ASB 206-14-132
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Consumable Material:
The following material is required to accomplish this bulletin, but may not require
ordering, depending on the operator’s consumable material stock levels. This material
may be obtained through your Bell Helicopter Textron Supply Center.
Part Number
Nomenclature
#1Fluid4ozultrachem
2110-07015-00
Assembly Fluid
Solvent, Drycleaning,
Degreaser
Qty
Reference *
1
1 (Note 1)
C-024
C-304
* C-XXX numbers refer to the consumables list in the BHT-ALL-SPM, Standard Practices Manual
Note:
1. This quantity represents one U.S. gallon. Two pints to one quart are required to
perform Part I or Part III of this ASB for each helicopter.
SPECIAL TOOLS:
None required.
WEIGHT AND BALANCE:
Not affected.
ELECTRICAL LOAD DATA:
Not affected.
REFERENCES:
BHT-206A/B-SERIES-IPB, Illustrated Parts Breakdown
BHT-206A/B-SERIES-MM, Maintenance Manual
BHT-206A/B/L-SERIES-CR&O, Component Repair and Overhaul Manual
TB 206-79-31, Freewheel Assembly Oil Line Filter, Installation of
PUBLICATIONS AFFECTED:
BHT-206A/B-SERIES-IPB, Illustrated Parts Breakdown, Chapter 63
BHT-206A/B-SERIES-MM, Maintenance Manual, Chapter 63
ASB 206-14-132
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ACCOMPLISHMENT INSTRUCTIONS:
Part I – Inspection and cleaning of filter 50-075-1 and restrictor 206-040-254-001
or 206-040-244-001.
1. Prepare the helicopter for maintenance.
-NOTEIt will not be necessary to remove the induction cowl to
accomplish the following.
2. Gain access to the area L/H aft of the transmission (26, Figure 1).
CAUTION
Immediately cap all lines, fittings, hose, and port once they
are open.
3. Disconnect/remove the following parts of the freewheel oil supply system:
a. For helicopters S/N 4 through 253 and 914 through 4690:
(1)
Disconnect and remove the hose (1).
(2)
Remove the filter 50-075-1 or the reducer (3). Discard the packing (4).
(3)
Disconnect the tube (5) from the restrictor (10).
(4)
Disconnect the tube (6) from the restrictor (2).
(5)
Remove the nut (7), washer (8), and restrictor (2) from the clip (9).
(6)
Remove the restrictor (10) from the restrictor (2). Discard the packing (11).
(7)
Inspect the restrictor (2) to determine if it is blocked.
(a) If the restrictor (2) is blocked, do step 4 and step 5 of Part I of this ASB.
(b) If the restrictor (2) is not blocked, do step 5 of Part I of this ASB. It is not
necessary to do step 4 of Part I of this ASB.
b. For helicopters S/N 254 through 913:
(1)
Disconnect and remove the hose (1).
ASB 206-14-132
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(2)
Remove the filter 50-075-1 or the reducer (3). Discard the packing (4).
(3)
Disconnect the wire terminal from the oil pressure switch (13).
(4)
Disconnect the connector from the oil pressure transducer (14).
(5)
Disconnect the tube (6) from the restrictor (21).
(6)
Remove the screw (15), clamp (16), spacer (17), and washer (18) from the
oil pressure transducer (14).
(7)
Remove the nut (19) and the washer (20) from the restrictor (21), and
remove the cross (22) with the attached items from the clip (23).
(8)
Remove the union (12) from the cross (22). Discard the packing (24).
(9)
Remove the restrictor (21) from the cross (22). Discard the packing (25).
(10) Inspect the restrictor (21) to determine if it is blocked.
(a) If the restrictor (21) is blocked, do step 4 and step 5 of Part I of this ASB.
(b) If the restrictor (21) is not blocked, do Step 5 of Part I of this ASB. It is
not necessary to do step 4 of Part I of this ASB.
4. If the restrictor (2 or 21) is blocked:
-NOTEDissassembly of the freewheel assembly is necessary only
to the extent to which the clutch, inner shaft, outer shaft, and
all bearings can be examined for condition.
a. Remove, disassemble, and visually inspect the freewheel assembly
(BHT-206A/B-MM, Chapter 63 and BHT-206A/B/L-CR&O, Chapter 63).
(1)
Note the condition of the oil that comes out of the freewheel assembly.
(2)
Report freewheel assembly inspection findings to Bell Helicopter Product
Support Engineering, Light Helicopters.
b. Reassemble and install the freewheel assembly (BHT-206A/B/L/-SERIESCR&O and BHT-206A/B-SERIES-MM, Chapter 63).
5. Clean and visually examine the following for condition:
ASB 206-14-132
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WARNING
Immediately cap, or otherwise protect from contamination, all
lines, hoses, fittings, and ports after cleaning. Blockage of
the restrictor (2 or 21) could cause the freewheel assembly
to malfunction.
Clean, inspect, and flush all removed fittings, restrictors, tubes, filter, and hose with
solvent (C-304) or equivalent.
-NOTEDirect the low air pressure toward the orifice side of the
restrictors (10, 2, and 21, as applicable).
a. With dry, filtered low air pressure (15 PSI maximum), remove all solvent from
the uncapped lines, hoses, and fittings.
b. Make sure that all the restrictors are free and clear of any contamination. Refer
to Table 1 for the diameters of the restrictor orifices.
6. Assemble and install all removed fittings, restrictors, filter, and hose as follows:
a. For helicopters S/N 4 through 253 and 914 through 4690:
CAUTION
Make sure all caps remain on all lines, hoses, fittings, and
ports until they are installed/connected.
-NOTEFor the correct location of the parts, refer to Figure 1 of this
ASB.
-NOTEThe use of assembly fluid (C-024) is the preferred lubricant
to use during the installation of the packings.
ASB 206-14-132
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(1)
Assemble the restrictor (10) with the restrictor (2) using new packing (11).
(2)
Attach the built-up restrictor (2) to the clip (9) with the washer (8) and the
nut (7).
(3)
Connect the tube (5) to the restrictor (10).
(4)
Connect the tube (6) to the restrictor (2).
-NOTEIf the filter 50-075-1 was not found installed during the
disassembly, it is recommended to install the filter
concurrently with Part I of this ASB. See Part II of this ASB
and TB 206-79-31 for filter effectivity.
-NOTEModel 206 helicopters S/N 2256 and subsequent shall have
the filter 50-075-1 installed.
(5)
Install the filter 50-075-1 or the reducer (3) in the transmission (26) using
new packing (4).
(6)
Attach the hose (1) to the filter 50-075-1 or the reducer (3) and the
restrictor (2).
b. For helicopters S/N 254 through 913:
CAUTION
Make sure all caps remain on all lines, hoses, fittings, and
ports until they are installed/connected.
-NOTEFor the correct location of the parts, refer to Figure 1 of this
ASB.
-NOTEThe use of assembly fluid (C-024) is the preferred lubricant
to use during the installation of the packings.
ASB 206-14-132
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(1)
Assemble the restrictor (21) with the cross (22) using new packing (25).
The orifice side of the restrictor is the side that is threaded into the cross.
(2)
Assemble the union (12) with the cross (22) using new packing (24).
(3)
Insert the restrictor (21) into the forward side of the clip (23) with the union
(12) facing inboard.
(4)
Install the washer (20) and loosely thread the nut (19) on the
restrictor (21).
(5)
Hold the clamp (16), spacer (17), and washer (18) in place on the threaded
insert on the transmission deck. Secure with the screw (15) (Figure 1).
(6)
Tighten the nut (19).
(7)
Attach the wire terminal to the transmission oil pressure switch (13).
(8)
Attach the connector to the transmission oil pressure transducer (14).
-NOTEIf the filter 50-075-1 was not found installed during the
disassembly, it is recommended to install the filter
concurrently with Part I of this ASB. See Part II of this ASB
and TB 206-79-31 for filter effectivity.
-NOTEModel 206A/B series helicopters S/N 2178, 2188, 2189,
2191 through 2254, and 2256 and subsequent shall have the
filter 50-075-1 installed.
(9)
Install the filter 50-075-1 or the reducer (3) in the transmission (26) using
new packing (4).
(10) Attach the hose (1) to the filter 50-075-1 or the reducer (3) and the
union (12).
ASB 206-14-132
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Part II – Replacement of the reducer with the filter 50-075-1.
-NOTEPart II of this ASB is applicable to helicopters S/N 1 through
2177, 2179 through 2187, 2190, and 2255 which have not
had TB 206-79-31 incorporated.
1. Prepare the helicopter for maintenance.
-NOTEIt will not be necessary to remove the induction cowl to
accomplish the following.
2. Gain access to the area L/H aft of the transmission (26, Figure 1).
WARNING
Immediately cap, or otherwise protect from contamination, all
lines, hoses, fittings, and ports after cleaning. Blockage of
the restrictor (2 or 21) could cause the freewheeling
assembly to malfunction.
3. Disconnect the upper end of the hose (1).
4. Remove the reducer (3).
5. Repeat Part I of this ASB.
6. Make sure the filter 50-075-1 was installed during the performance of Part I of this
ASB.
7. Make an entry in the helicopter logbook and historical service records indicating
compliance with Part II of this ASB.
ASB 206-14-132
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Part III – Filter and restrictors, recurring cleaning and inspection.
1. Perform Part I of this ASB.
2. Make an entry in the helicopter logbook and historical service records indicating
compliance with Part III of this ASB.
Table 1 – Restrictor Orifice Diameter
Figure 1,
Item Number
Restrictor
Part Number
10
206-040-094-001
2
206-040-244-001
21
206-040-254-001
Orifice Diameter
0.027 to 0.032 inch
(0.69 to 0.81 mm)
0.039 to 0.044
(0.99 to 1.12 mm)
0.039 to 0.044 inch
(0.99 to 1.12 mm)
ASB 206-14-132
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Figure 1
ASB 206-14-132
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