Checking and adjusting the air-mixture gap of Keihin carburetors (Audi 80 B3)

The air damper clearance should be adjusted after repairing the carburetor or after removing the upper part of the carburetor and if the cold engine does not accept gas well or there are dips in gas supply.

Adjustment

Remove the air filter.

Pull the starting (air) damper drive out completely. The damper lever "1" should be in contact with the stop (the air damper is closed).

Keihin-I carburetor: Connect a vacuum meter and a vacuum pump to the vacuum opening device. Create a vacuum with the pump at a pressure of 400 mbar. In this case, the vacuum opening device "Pulldown" should slightly open the air damper.

Keihin-II carburetor: Press the drive rod of the opening diaphragm of the device towards the diaphragm until it stops.

In this position, check the gap between the edge of the air damper and the wall of the carburetor diffuser with a suitable drill "2" and adjust if necessary. For values, see chapter "Repair characteristics".



Set the required clearance by bending the stop lever -arrow-.



The gap is too small: press the lever.

The gap is too large: tighten the lever.

Install the air filter.

(The article was copied from the website «AUDIMANUAL»)