Installation of the auxiliary valve for slightly opening the starting diaphragm
2 - connector, 3 - second membrane, 4 - tank
Auxiliary valve for slightly opening the starting diaphragm (scheme of work)
1 - adjusting screw, 2 - calibrated jet, 3 - starting diaphragm control shank, 4 - discharge pipeline, 5 - receiver, M1, M2 - membranes
The mechanism has a double-membrane vacuum control system for opening slightly, as well as a vacuum receiver and a connector.
Job
The engine is cold, the starting device is on, the springs push the membranes towards the carburetor body and act on the control tail, the starting diaphragm is closed. During engine start, the vacuum in the intake tube acts on the M1 membrane, which rests on the M2 membrane. The vacuum does not act on the M2 membrane immediately due to the use of a calibrated orifice in the passage between the chamber and the receiver. The starting diaphragm opens slightly, but to such an extent that enrichment immediately increases. The vacuum reaches the second chamber and the receiver is triggered, the spring is compressed by the membrane, the starting diaphragm control shank can move to the end of its stroke, and the starting diaphragm opens completely.
Connection of the second chamber and vacuum pipe in vehicles with automatic transmission
1 - calibrated jet, 2 - check valve
In cars with automatic transmission, the outer chamber is connected to the carburetor stand by means of a lag valve and a calibrated jet.