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Technical Information · issue 21 of 2003

Muffler with catalytic converter; Shroud; Ignition

IssueTI 21/2003

Part changes (5)

WasBecomesWhat the bulletin says
4140 140 0603 4140 140 0653 KM 55 C and the muffler with catalytic converter 4140 140 0603 for HL 45 C are being replaced by the new version 4140 140 0653.
4140 084 0900 4140 080 1600 Shroud 4140 084 0900 is replaced by the new version 4140 080 1600 on machines with loop 233TI032 KN handle.
4140 084 0902 4140 080 1601 Shroud 4140 084 0902 is replaced by the new version 4140 080 1601 for machines with bike handle (but not for HL 45).
1130 141 9001 4140 141 9002 Shroud) to protect it against The previous spark arresting screen 1130 141 9001 the higher temperature of the muffler with catalytic is replaced by the new version 4140 141 9002 in the converter.
4140 400 1303 4140 400 1305 Ignition module Ignition module 4140 400 1303 is replaced by the new version 4140 400 1305 in the new machines with catalytic converter.

Full text

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TI 21/2003 page 1
STIH)

Technical Information

                                                                       21.2003

  Brushcutters STIHL FS 45 C, FS 46 C, FS 55 C – Series 4140

  CombiEngine STIHL KM 55 C – Series 4140
  Hedge trimmers STIHL HL 45 C – Series 4232

  Contents
  1.   Muffler with catalytic converter
  2.   Shroud
  3.   Ignition module

  4.   Service notes
  5.   Summary

  1.     Muffler with catalytic converter

  In order to obtain a further improvement in machine                                6
  operation, the muffler with catalytic converter
  4140 140 0650 for FS 45 C, FS 46 C, FS 55 C and                      4

  KM 55 C and the muffler with catalytic converter
  4140 140 0603 for HL 45 C are being replaced by

  the new version 4140 140 0653.                                  3                       7
  The new muffler with catalytic converter makes it
  necessary to introduce additional cooling measures          1

  in the shroud, as well as a new ignition module.
  Mechanical design of the muffler                                               5

  1 = Deflecting plate 4140 140 7401
  2 = Gasket 4140 149 0604
  3 = Insulating pad 4140 146 9000
  4 = Muffler (not available separately as spare part)
                                                                                              233TI030 KN

  5 = Gasket 4140 149 0603                                         2
  6 = Flange 4140 145 1200
  7 = Gasket 4140 149 0602

  TI_21_2003_02_01_01.fm                                                         english / USA
)m~ge 2                                                                               Technical Information 21.2003

1.1       Deflecting plate                                       1.4   Maintenance and repair
                                                                 The catalytic converter does not require
                                                                 maintenance if the usual maintenance and care
                                                                 instructions are followed.
      8                                                          The catalytic converter is not serviceable.
                                                                 The two screws 9075 478 4159 (see 5. Summary,
                                                                 Item 9) are pre-fitted in the replacement muffler.

                                                                 2.    Shroud
                9

                                                   233TI031 KN

The deflecting plate 4140 140 7401 is fitted to
reduce the temperature at the outlet of the muffler.

                                                                                                                10
The deflecting plate is secured to the muffler with
screws (8) 9099 021 0805 and (9) 9022 421 0930.

1.2       Exhaust gasket

                                                                                                                      233TI033 KN
                             3
                                                                 New shrouds with integrated heat shield (10) and an
                    2
                                                                 additional insulating hose on the throttle cable are
                                                                 being introduced for machines with catalytic

                                                                 converter.
                                                                 Shroud 4140 084 0900 is replaced by the new
                                                                 version 4140 080 1600 on machines with loop
                                                   233TI032 KN

                                                                 handle. Shroud 4140 084 0902 is replaced by the
                                                                 new version 4140 080 1601 for machines with bike

                                                                 handle (but not for HL 45).
To reduce the temperature at the outlet, the exhaust             Only the new shrouds will be available as
gasket (2) 4140 149 0604 is fitted between muffler               replacements for all versions in future.

and deflecting plate in addition to the familiar
insulating pad (3) 4140 146 9000.                                2.1   Heat shield

                                                                 The heat shield (10) 4140 084 8300 is integrated
1.3       Spark arresting screen
                                                                 into the shroud (see 2. Shroud) to protect it against
The previous spark arresting screen 1130 141 9001                the higher temperature of the muffler with catalytic

is replaced by the new version 4140 141 9002 in the              converter.
new muffler with catalytic converter.

                                                                                                TI_21_2003_02_01_01.fm

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Technical Information 21.2003                                                                                       Page 3

2.2    Insulating hose                                                3.    Ignition module
                                                                      Ignition module 4140 400 1303 is replaced by the
                                                                      new version 4140 400 1305 in the new machines
                                                                      with catalytic converter. In the new ignition module,
                                                                      the speed is limited by adjusting the ignition timing.
                                                                      This protects the catalytic converter against thermal
                                                                      overloads.
                                                                      The previous ignition module 4140 400 1303
                                            13                        remains in use for all other machines.
                                          11
                                     12

                                                        233TI034 KN
                                                                      4.    Service notes

                                                                      The new muffler kit 4140 140 0651 must be used as
In the area below the muffler, the throttle cable is                  replacement for all machines with the previous
enclosed in an insulating hose (11) 4140 182 3300                     muffler with catalytic converter 4140 140 0650 or

in order to protect it against the higher temperature                 4140 140 0603.
of the muffler with catalytic converter.                              The muffler must be replaced completely with the kit

Service note:                                                         if repairs are required.
The throttle cable must be unhooked in order to fit
the insulating hose (refer also to the chapter
"Change throttle cable" in the Service Manual
"Machine Components 4140").
.     Unhook throttle cable from carburetor
.     Push insulating hose over throttle cable

      (from carburetor end)
.     Reconnect throttle cable
.     Slide insulating hose up to oblong hole (12) in

      engine compartment

.     Clamp insulating hose onto cable retainer (13)
      to secure it in position

TI_21_2003_02_01_01.fm
)m~ge 4                                                                  Technical Information 21.2003

5.     Summary
Item     Part name                               Previous             New                  Remarks
 1       Muffler (catalytic converter)           4140 140 0603        ---                  1)
 2       Muffler kit (catalytic converter)       4140 140 0650        ---                  1)
 3       Muffler kit (catalytic converter),      ---                  4140 140 0651
         replaces the previous version,
         including Items 5 – 10, 12, 13
 4       Muffler kit (catalytic converter),      ---                  4140 140 0653
         replaces the previous version,
         including Items 5 – 10, 14, 15

 5       Exhaust gasket                          4140 149 0602        4140 149 0602        4)
 6       Exhaust gasket                          4140 149 0603        4140 149 0603        4)
 7       Flange                                  4140 145 1200        4140 145 1200        4)

 8       Insulating pad                          4140 146 9000        4140 146 9000        4)
 9       Screw IS-D5 x 24                        9075 478 4155        9075 478 4159
         Screw IS-D5 x 24                        9075 478 4159        9075 478 4159        5)

10       Deflecting plate                        ---                  4140 140 7401
11       Stainless steel screw IS-M5 x 8         ---                  9022 421 0930
12       Screw DIN 7971 4.2 x 6.5                ---
                                                                   fo 9099 021 0805
13       Spark arresting screen                  1130 141 9001        ---                  2)
14       Spark arresting screen                  ---                  4140 141 9002
15       Exhaust gasket                          ---                  4140 149 0604

16       Shroud, including Item 18               4140 084 0900        4140 080 1600        1)
17       Shroud, including Item 18               4140 084 0902        4140 080 1601        1)
18       Heat shield                             ---                  4140 084 8300
19       Insulating hose                         ---                  4140 182 3300

20       Ignition module                         4140 400 1303        4140 400 1305        3)

         All other parts as before
Modification to be introduced continuously

Remarks
1) Previous version of part is no longer available from factory

2) Previous version of part remains available for older machines
3) Previous version of part remains available for other series
4) Part is still used in the new muffler

5) Only for HL 45

Last Technical Information on STIHL FS 45, FS 46, FS 55 and KM 55: 04.2003
Last Technical Information on STIHL HL 45: 36.2002

© ANDREAS STIHL AG & Co. KG, 2003                       Technical Documentation
                                                        D1/MTK-ja                                 7844

                                                                                  TI_21_2003_02_01_01.fm

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