Briggs & Stratton 272147 Repair Manual page 78

TM
Vanguard Twin-Cylinder OHV Liquid-Cooled Engine
Section 6 - Final Adjustments & Specifications
The following tools are required when making carburetor
adjustments.
1. An accurate tachometer, such as Tool
2. Tang bender, Tool
Fig. 187
Start engine and run it for approximately 5 minutes to
allow engine to reach operating temperature.
1. Move equipment control lever to "SLOW" position.
2. Hold throttle lever against idle speed screw
and temporarily adjust idle to 1200 RPM, Fig. 188.
3. While holding throttle lever, SLOWLY turn idle
mixture screw for #1 cylinder clockwise until
engine speed just starts to slow (lean mixture).
4. Then, turn idle mixture screw counterclockwise 3/
8 turn.
NOTE
: It may be necessary to readjust idle
speed screw to 1200 RPM before proceeding.
5. Adjust idle mixture screw for #2 cylinder as
described in steps 3 and 4.
6. Now, readjust idle speed screw to 1650 RPM.
#19389
.
#19480
7. Release throttle lever. Note RPM.
.
Fig. 188
8. If necessary, use tang bending Tool,
and bend governed idle tang to obtain 1850 RPM,
Fig. 189.
Fig. 189
9. IF CARBURETOR IS EQUIPPED WITH IDLE
MIXTURE LIMITER CAPS, INSTALL AT THIS
TIME.
a. Position limiter cap so that stop on limiter cap
is at mid point between stops on carburetor
body. Press limiter into position using knock
out pin , Tool
,
#19480
, Fig. 190.
#19135
Page 73