Technical Information · issue 43 of 1997
Carburetor; grommet; choke lever/throttle rod; car
Model STIHL 036 - Series 1125
IssueTI 43/1997
Engine family 1125
Part changes (1)
| Was | Becomes | What the bulletin says |
|---|---|---|
| 1125 120 0651 | 1125 120 0615 | The original carburetor 1125 120 0651 (C3A-S31) will be replaced by carburetor 1125 120 0615 (C3A-S39). |
Full text
Page 1 of 6
Technical Information
43.97
Model STIHL 036 - Series 1125
&RQWHQWV
1. Carburetor
2. Grommet
3. Choke lever/throttle rod
4. Carburetor box cover/guide
5. Muffler
Compliance with EPA regulations =see TI 27.97= is achieved with the modifications described below.
The factory applies the label shown below to all machines that conform to the latest standard.
Andreas Stihl IMPORTANT ENGINE INFORMATION
ENGINE FAMILY: A8XS. R ; Type: ; DISPL.: CC;M.D.:
THIS ENGINE CONFORMS TO U.S. EPA PHASE 1 EMISSION REGULATIONS
000TI013 KN
FOR ULGE´s. REFER TO OWNER´S MANUAL FOR MAINTENANCE
SPECIFICATIONS AND ADJUSTMENT. 967 34
1.=====Carburetor
The original carburetor 1125 120 0651 (C3A-S31)
will be replaced by carburetor 1125 120 0615
(C3A-S39). Limiter caps are fitted on the high
speed and the low speed screws of the new
carburetor to restrict the range of adjustment.
1.1====Carburetor parts/function
1=====High speed screw =with sealing ring= -
head knurled to hold cap in position
2=====Low speed screw =with sealing ring= -=========================================S
head knurled to hold cap in position 1
3=====Cap -=for high speed screw (red), 3
limits range of adjustment
4=====Cap=-=for low speed screw (white),
limits range of adjustment
138TI017 KN
5=====Springs -=keep adjusting screws in
preset positions 4 2 7 5
6=====Holder -=guides limiter caps
7=====Washers
)43.97 - 2
1.2===Standard setting
The machine comes from the factory with the
optimum carburetor setting and the limiter caps
fitted on the adjusting screws. This setting is
exactly the same as the standard setting described
in chapter "Adjusting Carburetor" in the owner’s
manual (H=3/4; L=1/4 open - starting from the 270°
lean stop in each case).
Corrections are possible only within a range of 270
138TI021 KN
degrees because two stops (arrows) on the limiter
caps restrict any further movement.
This enables the mixture to made leaner for opera-
tion at high altitudes, if necessary, and helps pre-
vent the mixture being enriched beyond EPA emis-
sion limits.
138TI018 KN
Correction of carburetor setting for higher alti-
WXGHV
If the engine runs unsatisfactorily, slight
readjustment may be necessary:
• Check standard setting
• Warm up the engine
• Turn the high speed adjusting screw (+) and
low speed adjusting screw (/) clockwise H L
(leaner) - 138TI019 KN
! If you make the setting too lean, the
maximum permissible engine speed will be
exceeded - risk of engine damage.
)================================================================================43.97 - 3
1.3=====Repair / servicing / basic setting
The limiter caps have to be removed to replace the
adjusting screws or clean the carburetor.
• Use suitable pliers to pull the limiter caps off
the + and / screws.
>= =The caps are damaged during the
==disassembly process and must not be
138TI020 KN
used again.
==If the limiter caps are removed in the
==course of a repair, fit new caps after
==adjusting the carburetor as specified.
1.3.1=Basic setting Ewithout caps)
After fitting the adjusting screws, carry out the
basic setting:
• Starting with screws hard against their seats: fo
H Z=lpen 1 full turn
L =Z=lpen 1 full turn H L
138TI022 KN
1.3.2=Fitting limiter caps
• ! Always fit QHZ limiter caps.
•=Fit the cap on the low speed screw first.
• Push home cap on low speed screw as
follows:
Slot vertical - position of stop as shown in
illustration.
138TI023 KN
• Push home cap on high speed screw as
follows:
Slot vertical - position of stop as shown in
illustration (rich stop).
• Push the limiter caps on to the adjusting
screws until they snap into position.
The position of the limiter caps (and the adjusting H
138TI024 KN
screws) is exactly the same as the standard
setting (see 1.2).
)43.97 - 4
1.3.3=Adjusting idle speed
• Set engine speed to 2,800 rpm with the idle
speed screw /$ .
! Use a tachometer.
1.4====Fuel =mix ratio
EPA approval was obtained with a fuel/oil mix
ratio of 50:1.
No emission measurements are available for
other mix ratios.
See also TI 27.97.
1.5====Federal Emission Control Systems
Utility Engines
See TI 27.97.
2.=====Grommet=============================================fo
A new grommet will be installed together with the
new carburetor described in chapter 1. The new
grommet 1125 123 7501 serves to guide the
carburetor screwdriver and replaces the original
grommet 1125 123 7506.
3.=====Choke lever/throttle rod
The choke lever and throttle rod were modified
in connection with the introduction of the new
carburetor. The part number of the choke lever
has been changed from 1125 185 2001 to
1125 185 2002, and that of the throttle rods from
1125 182 1500 to 1125 182 1501.
The new versions of the throttle rod and choke
lever can also be used for older machines.
4.=====Carburetor box cover/guide
Replacement carburetor box cover 1125 140 1903
will be supplied without the carburetor adjustment
symbol in future.
The guide is no longer included with the carburetor
box cover. Version 1125 121 7701 will now be
supplied as a replacement instead of version
1125 121 7700.
)=====================================================================43.97 - 5
5.====Muffler
Muffler 1125 140 0614 will be installed to comply
with EPA regulations. This muffler has a smaller
exhaust opening than the original version.
Furthermore, gasket 1125 149 0500 is fitted
between the upper and lower casings.
The muffler is now mounted to the crankcase with
IS-M5x25 spline screws instead of the previous
138TI026 KN
IS-M5x20 screws.
Service note
The new mufflers (with smaller exhaust opening)
may only be used for machines with EPA
approval. The original mufflers should still be used
in older machines.
)43.97 - 6
6XPPDU\
Item Part Name Original New Rem.
version version
============Carburetor C3A-S31A;=====================NNOR=NOM=MSRN=============JJJ===============NF
============Carburetor C3A-S39A;=====================JJJ=======================NNOR=NOM=MSNR=====OF
each of above includes items 1 to 8:
1 High speed screw 1125 122 6702 1125 122 6703 1)
2 Low speed screw 1125 122 6802 1125 122 6803 1)
3 Cap (red) --- 1125 121 2700
4 Cap (white) --- 1125 121 2701
5 Spring (2x) 1120 122 3005 1125 122 3000 1)
6 Washer (4x) --- 4135 121 8600
7 Holder --- 1125 122 4600
8 Valve jet 1125 121 5404 1125 121 5405 1)
9 Grommet 1125 123 7506 1125 123 7501 1)
10 Choke lever 1125 185 2001 1125 185 2002 3)4)
11 Throttle rod 1125 182 1500 1125 182 1501 3)4)
12 Carburetor box cover; 1125 140 1903 1125 140 1903 5)
including item 13:
13
14
Guide
Muffler
1125 121 7700
1125 140 0609
fo 1125 121 7701
1125 140 0614
1)6)
1)
15 Gasket --- 1125 149 0500
16 Spline screw (2x) 9022 371 1020 9022 341 1050 7)
All other carburetor parts as before
Modification to be introduced: in progress
5HPDUNV
1) Original version of part remains available as spare
2) Part must be used for EPA-approved machines only
3) Original version of part will be supplied from factory only as long as existing stocks last
4) New version of part also suitable for older machines
5) Only modified version of part is available from factory
6) New version of part not included in item 12
7) Original version of part remains available as spare for other models
Last Technical Information on model 036: 33.97
1997 Andreas Stihl Andreas Stihl - D1/MTK-al
Technical Documentation 6190 Page 2 of 6
Page 3 of 6
Page 4 of 6
Page 5 of 6
Page 6 of 6
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.