K 3500 Truck 4WD V8-393 6.5L DSL Turbo (1993)
Fuel Pressure: Testing and Inspection
Fuel Pump Pressure - Lift Pump
Pre-Inspection:
1. Make certain that there is fuel in the tank
2. Check for leaks at all fuel connections from the fuel tank to the injection pump
3. Start engine allowing it to run
4. Tighten any loose connections
5. Inspect all hoses for flattening or kinks that could restrict the flow of fuel
6. Check for air leaks or restrictions on the suction side of the fuel pump, which could seriously affect pump output.
Procedure:
1. Disconnect the fuel line at the inlet to the fuel filter assembly
2. Disconnect the fuel injection pump electric shut-off solenoid wire (pink wire).
3. Install a low pressure gage to the line
4. Crank or run the engine for 10 to 15 seconds
5. Fuel pressure should be 40 to 60 kPa (5.8 to 8.7 psi)
6. If the system fails to pass the test continue with inspection
Final Inspection:
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Fuel lines between fuel filter and tank for restrictions
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Fuel tank sending unit for restrictions
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If no restrictions are found, replace fuel pump
