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Home >> Sterling >> 1987 >> 825 S, 2.5 D >> Repair and Diagnosis >> Engine Performance >> System >> Fuel Evaporation System >> Testing >> 2-Way Valve
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2-Way Valve

  1. Remove fuel filler cap. Remove fuel vapor hose from liquid/vapor separator pipe. Connect vacuum/pressure pump with gauge to hose. Slowly draw vacuum while observing gauge.
  2. Vacuum should stabilize at .2-.6 in. Hg as 2-way valve opens. Reverse pump and gauge connections. Slowly pressurize vapor hose. Pressure should momentarily stabilize at 1.0-2.2 in. Hg as 2-way valve opens.
  3. If valve does not respond as outlined, check hose connections for leaks. If hose connections are okay, replace valve. Repeat test.