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Test 11, Distributor Vacuum Advance Check (Non-Turbo)

Vacuum Pump:





1. Ensure ignition timing and idle speed are set to specification.
2. Connect Digital Engine Analyzer 059-00004, and Advance Timing Analyzer 059-00006 or equivalent to engine.
3. Disconnect and plug distributor vacuum hoses.
4. Connect Rotunda Vacuum Tester 021-00037 to distributor vacuum advance, A chamber.
5. Start engine, and run at idle. Apply vacuum, while checking advance timing.
6. Connect Rotunda Vacuum Test 021-00037 to distributor vacuum retard, B chamber.
7. Apply vacuum while checking vacuum retard timing.
8. If timing is satisfactory, proceed to Test 12.
9. If timing is not satisfactory, replace distributor assembly or vacuum control unit as needed.