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Residual Pressure & Internal Leak Testing

NOTE: Pressure and leak testing does not include checking cold start valve.
  1. Open valve on pressure gauge. Turn on fuel pump for 30 seconds and then turn it off. Pressure can drop to minimum of 38 psi (2.7 kg/cm2 ) after 10 minutes. If pressure drops too far, inspect fuel pump check valve and all fuel fittings for leakage.
  2. If there are no leaks, check sensor plate clearance. If plate clearance is correct, replace diaphragm pressure regulator and repeat leak test. If pressure still drops too far, replace fuel distributor "O" rings.