Service Manual

ISB, ISBe and QSB (Common Rail [...] Injector
Section 6 - Injectors and Fuel Lines - Group 06 Page 6-75
To buy Cummins Parts and Service Manuals, Training Guides, or Tools go to our website at https://store.cummins.com
Test
Before attempting to isolate the leak, make sure that all
the high pressure fuel connectors are tightened to the
correct torque. Refer to Procedure 006-052 in Section 6..
If a connector is not tightened to the proper torque,
tighten the connector and perform the previous test again.
If the injector return flow is greater than the specified flow
rate, it is necessary to block off the fuel to one injector at a
time to determine the location of the leak.
With the engine not running, remove the fuel injector
supply line connecting the rail to cylinder number 1.
3.9L and 5.9L Engines
Install the injector leakage isolation tool, Part Number
3164325, on the rail where the number 1 cylinder fuel line
connects.
Torque Value: 30 N•m [ 22 ft-lb ]
4.5L and 6.7L Engines
Install the injector leakage isolation tool, Part Number
4918298, on the rail where the number 1 cylinder fuel line
connects.
Torque Value: 35 N•m [ 26 ft-lb ]