Fuel Injectors & Pumps

Section 8.7 MBE 900 Downstream (After Secondary Filter) Pressure Test

Section 8.7
MBE 900 Downstream (After Secondary Filter) Pressure Test

Perform the following, MBE Downstream (after secondary filter) Pressure Test, to determine the downstream pressure:‪

  1. Remove the engine trim panel. See current MBE 900 service manual (6SE414).
  2. Disconnect the fuel temperature sensor.
  3. Plug the disconnected fuel temperature sensor into the engine wiring harness and tie it up out of the way.
  4. Install the adaptor and seal from the fuel adapter parts kit (J-46377) .
  5. Attach a banjo fitting to the adaptor, and use that to connect the high-pressure fuel line (J-46372) and gauge (J-46378) to the adaptor.
  6. Open the fuel fill cap to release pressure in the fuel tank.
  7. Start the engine and run at a slow idle, 600-650 rpm.
  8. Read off the fuel pressure on the high-pressure gage. The gauge should read at least 430 kPa (62 psi). If the fuel pressure is too low, perform a fuel flow test.
  9. Increase the engine speed to 2500 rpm.
  10. Read off the fuel pressure on the high-pressure gage. The gauge should read from 400 to 650 kPa (58 to 94 psi). If the fuel pressure is within limits, and concern remains, do fuel flow test at nozzle holder, to try and resolve the issue. If the fuel pressure is too high, see troubleshooting table in current MBE 900 service manual (6SE414).
  11. Remove all test equipment. Reconnect fuel temperature sensor.
  12. Make sure the fuel cap is tightly closed and the vehicle has been restored to operating condition.


Unit Fuel Injectors and Unit Pumps Technician's Guide - 7SE500
Generated on 10-13-2008

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