← Service bulletins

Technical Information · issue 39 of 2001

STIHL 3/8" Oilomatic Picco Micro X Saw Chain: New

IssueTI 39/2001

Full text

Page 1 of 2

TI 39/2001 page 1
Technical Information

                                                                                                          39.2001
STIHL 3/8" Oilomatic Picco Micro X Saw Chain – Type 3999

New Chain Link Geometry

The previous type 3961 ripping chain will be

replaced by the new version 3999.
The new geometry of the chain links provides the                                            C
following benefits over type 3961:

.   25% longer wear life
.   10% higher cutting capacity

                                                                                       D
The shaded areas in the following illustrations show

                                                                                                                         689TI055 KN
the new profile.
Cutters                                                             .   2 mm longer top plate (C) for a longer wear life
                                                                    .   larger sliding face on bottom (D) for improved

                                                                        wear resistance
                    A
                                     B                              Drive Links

                                                      689TI054 KN

Compared to type 3961, the new cutters are higher
(A) and have
                                                                                                                         689TI056 KN

.   a steeper top plate rake angle (B) for a higher
    cutting capacity
                                                                    The drive links are no longer "necked" (E). The

                                                                    benefits are:
                                                                    .   increased breaking strength
                                                                    .   fatigue strength increased by 40%

TI_39_2001_01_01_01.fm                                                                                 englisch / english
)m~ge 2                                                                              Technical Information 39.2001

Oilomatic Oil Reservoir                                            Service Note
                                                                   Previous (3961) and new (3999) chain links must
                                                                   not be mixed together in one chain.

                                                     689TI058 KN

Drive links feature an additional Oilomatic oil
reservoir (F) for

.       improved chain lubrication
.       reduced cutting attachment wear

The STIHL Oilomatic chain lubricating system with
the additional oil reservoir is described in detail in
TI 39.96.                                                                 fo

Summary

Item         Part Name                                      Previous              New                   Remarks
    1        Right-hand cutter                              3961 662 0400         3999 662 0400         1)

    2        Left-hand cutter                               3961 662 0600         3999 662 0600         1)
    3        Drive link                                     3876 662 1000         3997 662 1000         1)

    4        Verbindungsglied eingerollt                    3876 660 6600         3997 660 6600         1)
    5        Verbindungsglied ohne Niet                     3876 662 1200         3997 662 1200         1)
Modification to be introduced: in progress

Remarks
1) Previous version of part remains available for chain type 3961

Last Technical Information on STIHL saw chain: 20.2001

© 2001 Andreas STIHL AG & Co.                                      Technical Documentation
  Waiblingen                                                       D1/MTK-bl                                   7355

                                                                                               TI_39_2001_01_01_01.fm

Page 2 of 2

TI 39/2001 page 2

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.

Report a transcription error →