This service manual contains detai-
led descriptions of all the repair
and servicing procedures specific
to this power tool series.
There are separate handbooks for
servicing procedures for stand-
ardized parts and assemblies that
are installed in several STIHL po-
wer tool models. Reference is
made to these handbooks in the
appropriate chapters in this
manual.
Servicing the carburetor is descri-
bed in the separate "Carburetors"
manual.
As the design concept of models
FS 25-4 and FS 65-4 is almost
identical, the descriptions and
servicing procedures in this
manual generally apply to both
machines. Differences are
described in detail.
You should make use of the
illustrated parts lists while carrying
out repair work. They show the
installed positions of the individual
components and assemblies.
Refer to the latest edition of the
relevant parts list to check the part
numbers of any replacement parts
needed.
Parts lists on microfiche and CD-
ROM are always more up to date
than printed lists.
A fault on the power tool may have
several causes. Apart from the
chapter "Troubleshooting" in this
manual, also consult the troubles-
hooting charts for all assemblies in
the "Standard Repairs, Troubles-
hooting" handbook.
Refer to the "Technical Informa-
tion" bulletins for engineering
changes which have been intro-
duced since publication of this
service manual. Technical informa-
tion bulletins also supplement the
parts list until a revised edition is
issued.
The special servicing tools men-
tioned in the descriptions are
listed in the last chapter of this ma-
nual.
Use the part numbers to identify
the tools in the "STIHL Special
Tools" manual.
The manual lists all special
servicing tools currently available
from STIHL.
Symbols are included in the text
and pictures for greater clarity.
The meanings are as follows:
In the descriptions:
•
= Action to be taken as
shown in the illustration
(above the text)
- = Action to be taken that
is not shown in the
illustration
(above the text)
In the illustrations:
= Pointer
= Direction of movement
Service manuals and all technical
information bulletins describing
engineering changes are intended
exclusively for the use of STIHL
servicing dealers. They must not
be passed to third parties.
Servicing and repairs are made
considerably easier if the machine
is mounted on assembly stand (2)
5910 890 3100 with the aid of
clamp (1) 5910 890 8800.
Secure the clamp to the assembly
stand with two washers and two
M8 nuts.
The complete machine can then
be swivelled to the best position
for the ongoing repair and this lea-
ves both hands free.
Always use original STIHL
replacement parts.
They can be identified by the
STIHL part number,
the
STIHL
logo
and the
STIHL parts symbol
(
The symbol may appear alone on
small parts.
2
FS 25-4, 65-4