4. Check the tightness of the valve : a) Losen the thumb screw (1). b) Start the engine, and let it turn over for a few minutes. c) Stop the engine : The pressure should not fall too quickly 5. Remove the 4005-T tester. Connect the fuel feed pipe to the Ill. CHECKING FOR LEAKS (fuel pump removed) 1. Close the feed hole «h» with a plug. Fit a rubber tube to the suction hole «g». 2. Submerge the pump completely in a vessel containing clean petrol. 3. Through the tube connected to hole «g», blow compressed air at a pressure of 100 to 300g/ cm? (1.4 to 4.2 psi).