Federal Low-Altitude and California Vehicles

SYSTEM TEST AT LOW ALTITUDES

NOTE: When disconnecting vacuum hoses, mark or label them to ensure proper routing while being reconnected.

The engine must be at operating temperature 95°C (205°F) before running this test.
1. Install a timing light, according to manufacturers' instructions.
2. Remove the air cleaner.
3. Disconnect the black vacuum hose from the carburetor primary emulsion well bleed nipple. Plug the nipple.

HAC System Test @ Low Altitude For Federal Low-Altitude And California Vehicles:

4. While running the engine at idle, apply vacuum with a hand vacuum pump to the vacuum hose.
Vacuum should hold.
5. Reconnect the vacuum hose to its original position.

Ignition Timing Mark:

6. Run the engine at idle and check ignition timing.
The vehicle should be running at Basic timing. Refer to SPECIFICATIONS.

HAC System Test @ Low Altitude:

7. While running the engine at idle, disconnect the white striped vacuum hose (two nipple side) from the HAC. Check that vacuum is felt by placing a finger at the end of the hose.
Vacuum should be felt. Proceed to the High-Altitude Compensator Test.

HAC System Test @ High Altitude For Federal Low-Altitude And California Vehicles:

SYSTEM TEST AT HIGH ALTITUDES

NOTE: When disconnecting vacuum hoses, mark or label them to ensure proper routing while being reconnected.

The engine must be at operating temperature before running this test.
1. Install a timing light, according to manufacturers' instructions.
2. Remove the air cleaner.
3. Disconnect the black vacuum hose from the carburetor primary emulsion well bleed nipple. Do not plug the nipple.
4. Connect a hand vacuum pump to the vacuum hose.
5. While running the engine at idle, apply vacuum. Vacuum should leak.
6. Reconnect the vacuum hose to its original position.

Ignition Timing Mark:

7. Run the engine at idle and check ignition timing.
The vehicle should be running at ACTUAL timing. Refer to SPECIFICATIONS.

Compensator Test @ Low Altitude:

HIGH-ALTITUDE COMPENSATOR TEST

Test Procedures to be done if at altitudes below 3,900 ft.

1. Disconnect the white striped vacuum hose (two nipple side) from the HA Compensator.
2. Connect a hand vacuum pump to the HA Compensator nipple.
3. Apply vacuum. Vacuum should leak.

Compensator Test @ Low Altitude:

4. Disconnect the black vacuum hose from the HA Compensator.
5. Connect a hand vacuum pump to the HAC nipple.
6. Apply vacuum. Vacuum should hold.

Compensator Test @ Low Altitude:

HIGH-ALTITUDE COMPENSATOR

Test procedures to be done if at altitudes above 3,900 ft.

1. Disconnect the white striped vacuum hose (two nipple side) from the HA Compensator.
2. Connect a hand vacuum pump to the HA Compensator nipple.
3. Apply vacuum. Vacuum should hold.

Compensator Test @ High Altitude:

4. Disconnect the black vacuum hose from the HA Compensator.
5. Connect a second hand vacuum pump to the compensator, via the black vacuum hose nipple.
6. With vacuum being held from step # 3, apply vacuum. Vacuum should leak when applied.

Testing The Check Valve:

CHECK VALVE

NOTE: When disconnecting vacuum hoses, mark or label them to ensure proper routing while being reconnected.

1. Remove the Check Valve.
2. Connect a hand vacuum pump to the check valve and check air tightness.
Vacuum applied to the dark blue side of the check valve, vacuum should leak.
Vacuum applied to the white side of the check valve, vacuum should hold.