Technical Information · issue 46 of 1994
Uprated engine
IssueTI 46/1994
From serial 31 578 923
Full text
Page 1 of 3
Technical Information
46.94
STIHL FC 72 Edger - Series 4133
Power increase
The edger FC 72 is available with a more powerful
engine unit from machine number X 31 578 923
onwards. The engine power has been increased
by approx. 15% to 0.8 kW (1.1bhp).
This increase has been achieved by:
●
●
changing the port timing
increasing the compression
● enlarging the cross-section of the intake port
● changing the shape of the transfer ports
● changing the shape of the gasket and
spacer flange
The new cylinder, gasket and spacer flange
versions are generally used as replacement parts.
Cylinder
The new cylinder differs from the original version
in that the cylinder base flange is approx. 3 mm
thicker and the intake cross-section is larger.
The original cylinder version was secured with
screws of size M5 x 16 while the new version is
10,5
secured with screws of size M5 x 20.
In order to ensure that they can be replaced, the
10
7
new versions of the cylinder and cylinder with
piston will be issued with size M5 x 20 screws for
replacement for a period of approx. three years.
15 19
356TI001
Original New
version version Page 2 of 3
Technical Information 46.94 - Page 2
Gasket
The window for the gas mixture is 19 mm wide in
the new gasket, as compared with only 16 mm in
the original version. The new gasket can be instal-
led in machines of the old version.
356TI002
Original gasket New gasket
Spacer flange
The opening of the new spacer flange is
19 mm wide on the side facing the cylinder. The
service notes must be observed when installing
the new spacer flange in machines of the old
version.
Service notes
Only replacement parts of the new type may
be used when repairing machines of the new
version, otherwise a deterioration in power output
and malfunctions must be expected.
The power output of machines of the original
version can only be increased to approx. 0.8 kW
(1.1 bhp) if all new parts are installed.
The new cylinder must be mounted with the size
M5 x 20 screws supplied in all cases; tightening
torque 10 Nm. Page 3 of 3
Technical Information 46.94 - Page 3
Summary
Part name Original New Key Rem. MOQ
version version H
Cylinder with piston; 4133 020 1200 4133 020 1201 1) 1
including items 1 and 2:
Cylinder; 4133 022 0500 4133 020 1250 1 1) 1
including item 2:
Spline screw
IS-M 5 x 16 (2x) 9022 341 0980 --- 2)
Spline screw
IS-M 5 x 20 (2x) --- 9022 371 1020 2 10
Other parts as before
Gasket 4133 129 0900 4133 129 0902 3) 1
Spacer flange assy.; 4133 120 2202 --- 3)
including items 3 to 6:
Spacer flange -*- 4133 121 1602 3 4) 1
Spline screw
IS-M 5 x 56 (2x) 9007 319 1121 9007 319 1121 4
Hexagon nut M 5 (2x)
Plug (2x)
9210 261 0700
4133 122 6900
9210 261 0700
4133 122 6900
5
6
Modification to be introduced from machine number X 31 578 923
Remarks
1) Original version of part is no longer available from factory
2) Original version of part remains available
3) Original version of part will be available from factory only as long as existing stocks lasts
4) Original version of part is not available as separate item
Last Technical Information on model FC 72: 05.94
Waiblingen, 25 November 1994 Andreas Stihl
D1/MTK-na 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.