Bowl Vent Valve: Testing and Inspection

Fig. 25 Testing The Bowl Vent Valve:

BOWL VENT VALVE INSPECTION:
1. Allow the engine to cool off completely to prevent fuel from gushing out of the BVV nipple.
2. Remove the air cleaner.
3. Disconnect the bowl vapor hose from the bowl vent valve (BVV) nipple and connect a hand vacuum pump to the BVV nipple.
4. Apply 3 in.Hg (20 kPa) of vacuum to the BVV and verify that when the engine is running vacuum holds and that when the engine is off vacuum leaks.
NOTE: Plastic vacuum pumps are highly susceptible to damage by fuel vapors. Use of a plastic pump may render the pump unserviceable.