Technical Information · issue 2 of 1998
066: Carburetor; grommet; cylinder with piston; fi
Model 066 Chainsaws - Series 1122
IssueTI 2/1998
Engine family 1122
Part changes (1)
| Was | Becomes | What the bulletin says |
|---|---|---|
| 1122 120 0616 | 1122 120 0618 | The original WJ-65 carburetor 1122 120 0616 will be replaced by the WJ-69 carburetor 1122 120 0618. |
Full text
Page 1 of 6
Technical Information
02.98
Model 066 Chainsaws - Series 1122
Contents
1. Carburetor
2. Grommet
3. Cylinder with piston
4. Filter cover
5. Muffler/gasket
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 WJ-65 carburetor 1122 120 0616
will be replaced by the WJ-69 carburetor
1122 120 0618. Limiter caps are fitted on the high
speed and the low speed screws of the new carbu-
retor to restrict the range of adjustment.
1.1 Carburetor parts/function
1 High speed screw -
head knurled to hold cap in position
2 Low speed screw - 5
head knurled to hold cap in position 4
3 Caps - limit range of adjustment 2
of H and L screws
3
4 O-rings - seal gap between screws
and carburetor body
137TI033 KN
5 Insert with mounting bores - molded stops
in the bores restrict adjustment travel 1
)MOKVU=J=O
1.2 Standard setting
The machine comes from the factory with the opti-
mum carburetor setting and the limiter caps fitted L
H
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 = 270° 270°
3/4; L = 1/4 open - starting from the
lean stop in each case).
137TI034 KN
Corrections are possible only within the 270°
adjustment range permitted by the integrally mol-
ded stops in the bores.
This enables the mixture to made leaner for
operation at high altitudes, if necessary, and helps
prevent the mixture being enriched beyond EPA
emission limits.
Correction of carburetor setting for higher
altitudes
If the engine runs unsatisfactorily, slight readjust-
ment may be necessary:
• Check standard setting
• Warm up the engine
• Turn the high speed adjusting screw (H) and
low speed adjusting screw (L) clockwise
(leaner) -
> If you make the setting too lean, the maxi-
mum permissible engine speed will be exceeded
and may result in engine damage.
1.3 Repair / servicing / basic setting
The limiter caps have to be removed to replace
the adjusting screws or clean the carburetor. Use
puller 5910 890 4500 for this purpose.
• Rotate limiter caps (adjusting screws)
counterclockwise as far as stop.
• Screw puller into cap counterclockwise until
137TI035 KN
cap comes off the adjusting screw.
>=
The caps are damaged during the
disassembly process and must not be
used again.
If the limiter caps are removed in the
course of a repair, fit new caps after
adjusting the carburetor as specified.
)MOKVU=J=P
1.3.1 Basic setting (without caps)
After fitting the adjusting screws, carry out the ba-
sic setting:
• Starting with screws lightly
against their seats:
H =Open 1 full turn
L =Open 1 full turn
1.3.2 Fitting limiter caps
• >=
Always fit new limiter caps.
• Insert the limiter caps in the bores as shown in
the illustration - check correct position of lugs - 1
see arrows.
•
Push the caps on to the adjusting screws until
they are flush with the insert (1).
137TI036 KN
LA
The position of the limiter caps (and the adjusting
screws) is exactly the same as the standard set-
ting (see 1.2).
1.3.3 Adjusting idle speed
• Set engine speed to 2,500 rpm with the idle
>
speed screw (LA).
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.
)MOKVU=J=Q
2. Grommet
Grommet 1122 123 7501, which guides the carbu-
retor screwdriver, will be installed together with the
new carburetor in place of the original grommet
1122 123 7500. The new grommet is shaped so
that fits into the recess (see arrow) and is then
flush with the limiter caps.
137TI037 KN
H L
3. Cylinder with piston
Modifications to the cylinder ports (different timing)
have optimized the combustion process.
These measures, and the changes to the muffler
described in chapter 5, reduce emissions and en-
able the specified limits to be met.
Bore, stroke and mounting dimensions of the cylin-
der remain as before.
The part number of the cylinder with piston
has been changed from 1122 020 1210 to
1122 020 1211. fo
4. Filter cover
A filter cover with a different carburetor setting
symbol (H=3/4, L=1/4) will be installed as standard.
Replacement filter cover 1122 140 1002 will be
supplied without setting symbols in future.
)MOKVU=J=R
5. Muffler/gasket
The size of the exhaust opening in the lower ca-
sing has been reduced from 16 mm (0.63 in) to 11
m
mm (0.43 in). The modified muffler has been assi- 11 m in)
gned a new part number (see Summary). (0.43
A new gasket 1122 149 0500 is fitted between the
muffler front and rear casings.
Service note
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.
137TI038 KN
A new gasket must be used whenever the upper
casing is removed.
)MOKVU=J=S
Summary
Item Part Name Original New Rem.
version version
Carburetor WJ-65; 1122 120 0616 --- 1)
Carburetor WJ-69; --- 1122 120 0618 2)
each of above includes items 1 to 6:
1 High speed screw; 1122 122 6706 1122 122 6703 1)
including item 2:
2 O-ring -*- -*- 3)
3 Low speed screw; 1122 122 6802 1122 122 6803 2)
including item 2:
2 O-ring -*- -*- 3)
4 Fixed jet 62 1122 121 5603 --- 1)
5 Fixed jet 64 --- 1122 121 5604
6 Cap (2x) --- 4203 121 2700
7 Grommet 1122 123 7500 1122 123 7501 1)
8 Cylinder with piston 1122 020 1210 1122 020 1211 1)
9 Filter cover 1122 140 1001
fo 1122 140 1002 1)
10 Muffler 1122 140 0609 1122 140 0613 1)
11 Gasket --- 1122 149 0500
All other parts as before
Modification to be introduced: in progress
Remarks
1) Original version of part remains available as spare
2) Part may only be used on machines with EPA approval
3) Part no longer available as replacement
Last Technical Information on model 066: 01.98
ã 1998 Andreas Stihl Andreas Stihl - D1/MTK-al
Technical Documentation 6210 Page 2 of 6
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