Prelude L4-1958cc DOHC (1989)
Two-Way Valve: Testing and Inspection
Fig. 106 Vacuum Testing Two-Way Valve
1.
Remove the fuel filler cap.
2.
Install a "T" fitting in the vapor line between the fuel tank and the two-way valve, Fig. 106, and connect a vacuum pump to the fitting.
3.
Watch the gauge while slowly applying vacuum. Vacuum should stabilize at 5 - 15 mm Hg (0.2 - 0.6 in. Hg).
If the valve opens above or below specification, replace it and re-test.
4.
Switch the hose from the vacuum port to the pressure port on the vacuum pump.
Fig. 107 Pressure Testing Two-Way Valve
5.
Watch the gauge while slowly applying pressure to the two-way valve, Fig. 107,. Pressure should stabilize at 10 - 35 mm Hg (0.4 - 1.4 in. Hg). If
the valve opens above or below specification, replace it and re-test.