Carburetor Synchronization

Fig. 37 Connecting a Vacuum Pressure Gauge For Carburetor Synchronization:

1. Remove the red braided hose marked "purge" from the charcoal canister and connect a vacuum gauge.
2. Start engine and allow it to run until the cooling fan comes on.

Fig. 38 Throttle Stop And Synchronization Screws:

3. Raise engine speed to 3000 rpm by turning the throttle stop screw.
4. While watching vacuum gauge, pinch off the smooth red vacuum line under the choke hosing.

Expected result:
No change. If OK proceed to step 6. If not OK continue.

5. If the desired result was not achieved, turn synchronization screw and retest. [1]
6. Remove vacuum gauge and reconnect canister purge hose.
7. Reset idle using throttle stop screw.

[1] It is not possible to predetermine the direction the synchronization screw must be turned. Turn the screw 1/4 turn either direction and retest. If the vacuum gauge changed less than in the original test, screw rotation is correct.