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Technical Information · issue 14 of 1996

Backplate; fan casing; container; fuel hose/gromme

Model BR 320, 400 Blowers and SR 320, 400 Mistblowers - Series 4203

IssueTI 14/1996

Part changes (2)

WasBecomesWhat the bulletin says
4203 700 3800 4203 700 3850 The original backplate 4203 700 3800 will be 2 replaced by the version 4203 700 3850.
4221 353 9201 0000 989 0516 The grommet 4221 353 9201 in the fuel hose kit has been deleted and replaced by grommet 0000 989 0516.

Full text

Page 1 of 4

TI 14/1996 page 1
Technical Information 

                                                                                                14.96

Model BR 320, 400 Blowers and SR 320, 400 Mistblowers  -  Series 4203

&RQWHQWV

1. Backplate

2. Fan casing (outer)
3. Container (filler cap, strainer)
4. Fuel hose/grommet

5. Carburetor
   (high speed screw, low speed screw)
6. Pressure pump (oil seal)                                                             1

                                                                                        5 3
                                                                                            4
1.=Backplate

In future, models BR/SR 320, 400 will come with
a new backplate.
The original backplate 4203 700 3800 will be                                            2
replaced by the version 4203 700 3850.

Included in the scope of supply of the new
backplate are three springs 4203 708 0800,
three retaining plates 4203 706 1100,
three IS P6 x 21.5 spline screws and

three IS P6 x 19 spline screws.

                                                                                                        352TI001 KN
The annular buffers 4203 790 9900 are no longer
installed but will remain available as replacements.

6XPPDU\

Item         Part Name                                 Original                 New                Rem.
                                                       version                  version

1            Backplate;                                4203 700 3800            4203 700 3850      1)
             including items 2 to 5:
2            Retaining plate

                                                       ---                      4203 706 1100
3            Spring                                    ---                      4203 708 0800
4            Spline screw IS P6 x 21,5                 ---                      9074 478 4475
5            Spline screw IS P6 x 19                   9074 478 4425            9074 478 4425      2)
6            Annular buffer                            4203 790 9900            ---                3)
7            Safety retainer                           1121 791 1200            ---                3)
8            Pan head screw                            1121 791 6105            ---                3)
Modification to be introduced: in progress

5HPDUNV
1) Original version of part will be supplied only until existing stocks are exhausted
2) Quantity changed from 6 to 3
3) Original version of part remains available for older machines

Page 2 of 4

TI 14/1996 page 2
Technical Information 14.96  -  Page 2

2.=====Fan casing =outer

In connection with the above modification the blind
hole in the outer fan casing will be changed to a
through-hole for mounting the spring.
The part number remains unchanged.

3.=====Container =SR 320, 400 only

The filler cap and strainer will be modified to further
improve operator comfort. The increase in strainer
capacity helps quicken and simplify the refilling

process.

                                                                                                         352TI002 KN
                                                                Left:     Original version
                                                                Right:   fo
                                                                          New version
6XPPDU\

Item          Part Name                                   Original                 New              Rem.
                                                          version                  version

1             Container;                                  4203 700 0800             4203 700 0800
              including item 2:

2             Filler cap;                                 4203 700 0900             4203 700 0902   1)
              including item 3:
3             Sealing ring                                4203 709 2000             4203 709 2000

Q=============Pressure pump mounting kit;=================QOMP=MMT=NMNS=============QOMP=MMT=NMNS===OF
              including item 5:

5             Filler cap;                                 4203 700 0901             4203 700 0903   1)
              including item 6:
6             Sealing ring                                4203 709 2000             4203 709 2000

7             Strainer                                    4203 700 8802             4203 700 8810   3)

Modification to be introduced: in progress
5HPDUNV

1) Original version of part not longer available from factory
2) Only modified version of part is available from factory
3) Original version of part remains available for older machines

Page 3 of 4

TI 14/1996 page 3
Technical Information 14.96  -  Page 3

4.=====Fuel hose/grommet

The grommet 4221 353 9201 in the fuel hose kit
has been deleted and replaced by grommet
0000 989 0516. The ends of the hose
4203 358 7600 will not be tapered when the new
grommet is introduced.
The length of the hose has been changed from
295 mm to 272 mm.

                                                                                                    352TI003 KN
                                                            Left:    Original version
                                                            Right:   New version

6XPPDU\

Item          Part Name                              Original                 New             Rem
                                                     version                  version
1             Fuel hose kit;
              including items 2 and 3:
                                                     4203 007 1017            4203 007 1017

2             Grommet                                4221 353 9201            0000 989 0516   1)
3             Hose                                   4203 358 7600            4203 358 7600   2)

Modification to be introduced: in progress
5HPDUNV

1) Original version of part remains available for other models

2) Only modified version of part is available from factory

5.=====Carburetor

New high and low speed screws will be installed in
HD-4 and WT 230 carburetors (4203 120 0601 and
4203 120 0605) to optimize fine tuning. Their type

designations have been changed to HD-4 A and
WT 230 A respectively.

Service note
Only the new versions of the high and low speed
screws may be used in the new versions of the
carburetors.

Page 4 of 4

TI 14/1996 page 4
Technical Information 14.96  -  Page 4

6XPPDU\

Item         Part Name                                Original                  New             Rem.
                                                      version                   version
1            Carburetor HD-4;                         4203 120 0601
2            Carburetor HD-4 A;                                                 4203 120 0601   1)
             each of above includes
             items 3 and 4:
3            High speed screw                         4116 122 6700             4203 122 6701   2)
4            Low speed screw                          4116 122 6800             4203 122 6801   2)

5            Carburetor WT 230;                       4203 120 0605

6            Carburetor WT 230 A;                                               4203 120 0605   1)
             each of above includes
             items 7 and 8:

7            High speed screw                         1120 122 6705             4130 122 6700   2)
8            Low speed screw                          4119 122 6801             4203 122 6802   2)
Modification to be introduced: in progress

5HPDUNV
1) Only modified version of part is available from factory
2) Part remains available for other models                          fo
6.=====Pressure pump

Oil seal 9640 003 0950 will be installed to further
improve operation of the pressure pump
4203 700 0600. There will be no groove in the
pump housing 4202 701 0500 in future.

In the event of a repair the space between the ball
bearing and oil seal should be packed with gear

lubricant (0781 120 1109).

6XPPDU\

Item         Part Name                                Original                  New             Rem.
                                                      version                   version

1            Pressure pump;                           4203 700 0600             4203 700 0600   1)

             including items 2 and 3:
2            Oil seal                                 9638 003 0940             9640 003 0950   2)1
3            Pump housing, top                        4202 701 0500             4202 701 0500   1)

Modification to be introduced: in progress
5HPDUNV

1) Only modified version of part is available from factory
2) Original version of part will be supplied only until existing factory stocks are exhausted

Last Technical Information on models BR/SR 320, 400: 21.94

                                                             Andreas Stihl - D1/MTK-al
 1996 Andreas Stihl                                         Technical Documentation             5749

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