I have a question!,
I have test the vacuum on the distributor(vacuum-unit),and the result was 0-hg on idle!
When the engine idle....there is no vacuum to the vacuum-unit?
Can somebody tell me how it works??.
At the carb, disconnect the vacuum line that goes from the carb to the vacuum advance unit.
Connect the hose from your vacuum tester/gauge to the port on the carb (the port that you just removed the vacuum line from).
Start the engine.
If the port on the carb that the vacuum gauge is connected to is "Ported Vacuum" there will be very little - if any, vacuum until you speed up the engine. If the port the gauge is connected to is "Manifold Vacuum", the gauge will show a reading.
The vacuum unit on the distributor will not produce any vacuum at all. It responds to vacuum from the engine.
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