b. Cleaning and Inspection.
(1) Clean vacuum control valve.
pressure gage should read 80-to 100-pounds per square
(2) Inspect for defects. Replace defective
inch. If this pressure is not indicated, proceed to the next
vacuum control valve.
step after repositioning transmission selector control to
(1) Install vacuum control valve as shown in
(5) Connect a vacuum gage in the carburetor-to-
vacuum control valve line and repeat step (4).The
(2) Adjust jam nut to obtain 3/8 inch distance
vacuum gage should read 5.8-to 6.8-inches of mercury
from face of transmission case to face of vacuum control
at 1,000 revolutions per minute. A low vacuum gage
reading indicates a leak at the carburetor gasket, or at
the carburetor-to-vacuum control valve, or in the vacuum
control valve. Tighten connections or replace vacuum
(2) Remove pipe plug at rear of transmission
control valve if necessary. A high vacuum gage reading
indicates the carburetor vent is plugged or the line has
restrictions. Remove restrictions as applicable.
(3) Set hand brake and operate engine at 1,000
(6) Check installation of vacuum control valve to
obtain correct pressure readings as indicated in
paragraph (4) and (5) above. One-half turn of vacuum
control valve is permissible to obtain correct pressures.
(7) Shut off engine and remove gages.
Do not operate engine for more than 10
seconds during this next step.
(4) Apply service brakes and place transmission
selector control to "D" position. The
Figure 4-4. Transmission rear servo adjuster and test port