Technical Information · issue 38 of 1994
New air filter
Model 021, 023, 025 Chain Saws - Series 1123
IssueTI 38/1994
Engine family 1123
Part changes (3)
| Was | Becomes | What the bulletin says |
|---|---|---|
| 1123 120 1605 | 1123 120 1651 | filter 1123 120 1605 has been replaced by the Left: Original air filter new version 1123 120 1651. |
| 1123 034 3000 | 1123 034 3005 | The original piston ring 1123 034 3000 will be replaced by the new version 1123 034 3005 which is made from a different material. |
| 9646 945 0340 | 9646 945 0350 | The original O-ring 9646 945 0340 will be replaced by the new version 9646 945 0350. |
Full text
Page 1 of 4
Technical Information
38.94
Model 021, 023, 025 Chain Saws - Series 1123
Contents
1. Air filter (larger filter area)
2. 021, 023 piston ring (material)
3. Oil pump connector (O-ring)
1. Air filter
A modified bisectional air filter will be installed as
standard equipment. The bottom half of the filter is
screwed to the carburetor; the top snaps on to the
bottom half.
Benefits of the new filter:
• Larger filter surface area;
this means less maintenance
• Snap lock easily released when
top half has to be removed for cleaning.
The air filter 1123 120 1620 previously supplied
as a spare will remain available in addition to the
new version 1123 120 1650. The original flocked
filter 1123 120 1605 has been replaced by the Left: Original air filter
new version 1123 120 1651. Right: New air filter
1.2 Notes on installation
Different procedures are necessary depending
on the type of filter fitted in the machine.
1.2.1 Machines with foam filter element
• Unscrew the nuts.
• Remove the filter housing (1).
• Fit the modified air filter (2).
• Screw on the nuts and torque down to 2 Nm
(1.5 lbf.ft).
• Refer to 1.2.3 "Carburetor box cover". Page 2 of 4
Technical Information 38.94 - Page 2
1.2.2 Machines with box filter
• Remove the box filter.
• Unscrew the nuts from the studs.
• Fit the modified air filter.
• Screw on the nuts and torque down to 2 Nm
(1.5 lbf.ft).
• Refer to 1.2.3 "Carburetor box cover".
1.2.3 Carburetor box cover
The modified air filter can only be installed
together with a carburetor box cover without
ribs. Carburetor box covers with ribs were installed
up to mid-1992. They are found on machines with
both foam and box filters.
There are three possible methods of repairing
these machines: fo
Ribs in carburetor box cover
a) Install air filter 1123 120 1620 (still available
as spare) with the existing carburetor box cover
(with ribs).
b) Install a carburetor box cover without ribs along
with the modified air filter.
c) Use side cutters, pliers or other suitable tool to
remove ribs from the existing carburetor box
cover and carefully deburr the cover. Deburring
is very important to ensure that the filter fabric
cannot be damaged when the carburetor box
cover is fitted.
The clearance between the top edge of the air
filter and the carburetor box cover is only a few
millimeters. Installed position of air filter
... Page 3 of 4
Technical Information 38.94 - Page 3
Summary
Part Name Original New Key Rem. MOQ
version version H
Air filter kit; 1123 007 1007 --- 1)
including items 1 to 3:
Air filter; 1123 120 1620 1123 120 1650 1 2) 1
including item 4:
Slotted nut 1123 141 8300 --- 2 2)
Hexagon nut M5 9210 260 0700 --- 3 3)
Flange nut --- 9216 261 0700 4 10
Air filter, flocked; 1123 120 1605 1123 120 1651 1) 1
including item 4:
Modification to be introduced: in progress
Remarks
1) Original version of part is no longer available from factory
2) Original version of part remains available for older machines
3) Original version of part remains available for other models
2. Piston ring (021, 023)
The original piston ring 1123 034 3000 will be
replaced by the new version 1123 034 3005 which
is made from a different material.
Summary
Part Name Original New Key Rem. MOQ
version version H
Cylinder with piston; 1123 020 1201 1123 020 1214 1) 1
including items 1:
Piston D 40; 1123 030 2000 1123 030 2001 1 1) 1
including item 2:
Piston ring 1123 034 3000 1123 034 3005 2 1) 2
Modification to be introduced: in progress
Remarks
1) Original version of part is no longer available from factory Page 4 of 4
Technical Information 38.94 - Page 4
3. Oil pump connector
The original O-ring 9646 945 0340 will be replaced
by the new version 9646 945 0350.
Summary
Part Name Original New Key Rem. MOQ
version version H
Connector; 1123 640 2900 1123 640 2900 1)
including item 1:
O-ring 6 x 1.5 9646 945 0340 --- 1 2)
O-ring 6.07 x 1.78 ---
fo 9646 945 0350 1 10
Modification to be introduced: in progress
Remarks
1) Unmodified version of part will be supplied until existing factory stocks are exhausted
2) Original version of part remains available for other models
Last Technical Information on models 021, 023, 025: 26.94
Waiblingen, October 6, 1994 Andreas Stihl
D1/MTK-st Technical Documentation Extracted from the manufacturer's 2012 service catalogue. Most of these PDFs embed fonts with a shifted character map, so the text above was recovered rather than copied — read it as a faithful but imperfect transcription, and treat the page image above each block as the authority where the two disagree — the figures exist only there, because they are vector drawings that text extraction cannot keep.