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Home >> GMC >> 1983 >> Forward Control 6.2 J, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Fuel Injection System - Diesel >> Testing >> Injection Pump Housing Fuel Pressure
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Injection Pump Housing Fuel Pressure

  1. Remove injection pump and drain all fuel. Connect an air supply line to fuel inlet fitting. Be sure air supply is clean and dry.
  2. Seal the return line fitting. Completely immerse pump assembly in a container of clean test oil.
  3. Apply 20 psi (1.4 kg/cm2 ) to pump. Leave pump immersed for 10 minutes to allow any trapped air to escape. Watch for leaks after 10 minutes.
  4. If no leaks are noticed after 10 minutes, reduce air pressure to 2 psi (.14 kg/cm2 ) for 30 seconds. If there are still no leaks, increase pressure to 20 psi (1.4 kg/cm2 ) again.
  5. If no leaks are observed, pump is serviceable. If leaks are observed, pump must be exchanged for replacement unit.