272144 Vanguard Twin Cylinder OHV BRIGGS & STRATTON.pdf

4. While holding throttle lever, SLOWLY turn idle
mixture screw for #1 cylinder CLOCKWISE until
engine speed just starts to slow (LEAN mixture).
a. 1750 RPM – Governed Idle Spring #805453
(RED).
b. 1100 RPM – Governed Idle Spring #805454
(WHITE).
NOTE: Parts removed for clarity.
Fig. 19
5. Then turn idle mixture screw (3) COUNTER-
CLOCKWISE 3/8 turn, Fig. 20.
Fig. 21
NOTE: It may be necessary to re-adjust idle speed
to 1200 RPM before proceeding.
6. Adjust idle mixture screw for #2 cylinder as
described in steps 4 and 5.
7. If necessary, re-adjust idle speed screw to RPM
shown below.
a. 1200 RPM – Governed Idle Spring #805453
(RED).
b. 900 RPM – Governed Idle Spring #805454
(WHITE).
8. Release throttle lever. Note RPM.
10. If carburetor is equipped with idle mixture limiter
caps, install at this time.
a. Position limiter cap (8) so that stop on limiter
cap is at mid point between stops on carburetor
body. Press limiter into position using
Knock Out Pin #19135 (7) as shown in,
Fig. 22.
b. Repeat for other idle mixture valve.
Fig. 22
Fig. 20
9. If necessary, use Tang Bender #19352 (6),
Fig. 21. Bend governed idle tang LEFT to
INCREASE (4), right to DECREASE (5) engine
speed to obtain RPM shown:
11. With equipment control lever in SLOW position
and engine running at governed idle, use Tang
Bender #19352 (10), to bend throttle restrictor
tang (9) so that it just contacts governor lever
(11), Fig. 23.
12. Move equipment control to FAST position.
Engine should accelerate smoothly. Re-adjust
idle mixture valve 1/8 turn richer if necessary.
15