HOUSING 6G6263 - Caterpillar

Illustration 3 g06088551
Fuel Injector Cooling Circuit
(5) Return Lines
(6) Supply Lines
Table 6
Troubleshooting Test Step Value Result
11. Check for a Leak into the Injector Cooling Circuit
A. Turn the keyswitch to the OFF position.
B. Disconnect the injector cooling circuit supply line from the injector cooling supply orifice fitting.
C. Cap the injector cooling supply line end with contamination control part number 9U-7079 Tapered Cap/Plug.
D. Install a threaded plug on the injector cooling circuit orifice fitting to seal orifice so no fuel comes from the manifold during cranking. Use 6V-9831 Cap As.
E. Disconnect the injector cooling circuit fuel return lines from the joints to the cylinder heads. The injector cooling circuit return line is on the left side of the cylinder head and connects to the lower injector cooling fuel rail
F. Turn the keyswitch to the ON position.
G. Connect Cat ET.
H. Using Cat ET set the "Fuel Injection Enable Status" in the configuration screen to "Disabled".
Note: This must be done to prevent damage to the fuel injectors.
I. Crank the engine for 30 seconds for 3 cycles.
Note: A prelube cycle must complete prior to allowing the engine to crank on some engines. The prelube cycle could take up to 30 seconds. The engine will only crank for 30 seconds at a time to protect the starter. Then the engine will require 30 seconds to cool back down.
K. Inspect each of the injector cooling circuit return ports on the cylinder head for signs of fuel leakage.
Note: Fuel leakage may occur, be prepared to collect leaking fuel.
Fuel Leak
Result: There was no fuel leakage detected.
Repair: Using Cat ET set the "Fuel Injection Enable Status" in the configuration screen to "Enabled".
Reconnect the speed/timing sensors.
Reconnect all the injector cooling circuit return lines that were removed.
Proceed to Test Step 12.
Result: A fuel leak from the injector cooling circuit return port was detected.
Repair: A quill tube leaking into the injector cooling circuit has been detected.
Release the pressure in the high-pressure rail by loosening the end plug on one of the last 2 fuel accumulators. Refer to Testing and Adjusting, "Fuel Rail Pressure - Release" for instructions on how to release the pressurized fuel.
Verify that the "Fuel Rail Pressure" reading in ET is 0 8 MPa (1160 psi) prior to servicing the fuel system.
Remove the quill tube and the injector and inspect the mating surfaces for signs of damage. Replace if necessary.
Reassemble the fuel system. Using Cat ET set the "Fuel Injection Enable Status" in the configuration screen to "Enabled".
Proceed to Test Step 12.
12. Perform a "Fuel