Can a distributor vacuum advance unit be adjusted?

Can a distributor vacuum advance unit be adjusted?

Not all distributor vacuum advance units are adjustable. Non adjustable units have a fixed calibration from the manufacturer and no adjustment is possible. Car exhaust fumes are toxic; work only in a well-ventilated area. Keep body parts, tools and loose clothing away from moving engine parts.

What’s the best way to replace a vacuum distributor?

If you need the old one make sure it’s working by sucking on the vacuum fitting. Setting the point gap. Note the points’ wiper is on the tip of the distributor cam. Stop now and set the point gap! While the distributor is out and easy to work around, put it on the bench or in a vise and set the point gap to the correct specification.

How do you change the timing on a vacuum pump?

Disconnect the vacuum pump and insert a 3/32 Allen wrench into the port on the vacuum advance where the hose connects. There is a small adjusting screw in the vacuum advance. Turn the screw clockwise to decrease the vacuum advance and counterclockwise to increase the advance.

How do you remove a vacuum advance hose?

Remove the vacuum advance hose plug and reconnect the hose to the distributor. Remove the vacuum advance hose at the carburetor. Connect the long-hosed vacuum gauge to the carburetor’s vacuum advance port.

What to do if your vacuum line is inoperative?

Plugging the distributor end of the vacuum line is irrelevant at this point — it’s inoperative anyway. Prevent the carburetor from sucking air through the vacuum line so it idles evenly while making the idle adjustment. So you pull the vacuum line off and plug the carby end. The carburetor creates the vacuum, the distributor uses it.

What happens if the advance vacuum line is not working?

If the advance vacuum line is not working, the advance should stay reasonably steady — only changing with the revs. If this is the case, the distributor is definitely a dual advance (vacuum/centrifugal) operating like a 009 distributor (centrifugal only), and this would explain the hesitation you are still getting.

Where does the vacuum line go in a VW?

Let me make sure I have this straight: The MAIN vacuum line attaches to the port on the vacuum chamber at the rear (actually mine comes out of the side pointing toward the fuel pump, but that’s okay) and goes to the vacuum port on the left side of the carby under the stepped cam.

How to set base timing on a vacuum advance distributor?

BEFORE doing any base timing settings, MAKE SURE where the point dwell reading is, as changing that after the base timing is set WILL affect the base timing. IF it’s still a points distributor. Look at the FSM distributor advance specs. Then add the base timing to that number.