505 L4-1971cc XN (1983)
Fig. 12 Connecting vacuum pump to electro valve
Diagnosis
1.
Disconnect T-hose, Fig. 11, from electro valve.
2.
Connect a suitable hand held vacuum pump, Fig. 12, to the electro valve.
3.
Start engine and increase engine speed slightly. Pump gauge should indicate vacuum.
4.
Release throttle and allow engine to return to idle. No vacuum should be indicated.
5.
If vacuum is obtained with engine idling, check condition and/or adjustment of micro switch, operation of twin speed relay, Fig. 8, and electro
valve.