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Lower Chamber (Differential) Pressure - Part I

  1. Close valve on pressure gauge. Activate fuel pump with jumper switch. Leave differential pressure regulator disconnected. Differential pressure reading should be 2.9-7.0 psi (.2-.5 kg/cm2 ) less than system pressure. If pressure is not correct, disconnect lower chamber return line and hold open end over measuring container.
  2. Close open port to diaphragm pressure regulator. Activate fuel pump with jumper switch. Fuel volume should be .14-.16 qts. (.13-.15L) for period of 1 minute. If volume is correct, replace differential pressure regulator. If volume is not correct, replace fuel distributor.