2006/11/20 Caterpillar

Engine:

C6.6 (S/N: 6661-UP)

C4.4 (S/N: 4441-UP)

Engine News SEBD9422, 20 November 2006, "New Tooling for the New Air in Fuel and Fuel Pressure Test Procedures". Disregard this article. See the replacement article that follows.

Description of Change: The test for air in fuel for C6.6 and C4.4 engines has been improved. A new fuel pressure test has been introduced.

Adaptable To: The new test kit replaces the previous test kit.

Table 1

Required Tools
Tool	Part Number	Part Description	Qty
A	124-6275	Hose clamp	4
	215-9513	Connector	2
	158-6067	Hose	2
	102-5758	Hose end	2
	3P-2234	Nipple	2
	3P-2233	Coupler	2
	2P-8278	Sight gauge	1
B	6V-1739	Tee	1
	8T-0854	Pressure indicator	1
	3P-2234	Nipple	1
	3P-2233	Coupler	1

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NOTICE
Ensure that all adjustments and repairs that are carried out to the fuel system are performed by authorised personnel that have the correct training. Before begining ANY work on the fuel system, refer to Operation and Maintenance Manual, SEBU8120, "General Hazard Information and High Pressure Fuel Lines" and Operation and Maintenance Manual, SEBU8180, "General Hazard Information and High Pressure Fuel Lines" for safety information. Refer to Systems Operation, Testing and Adjusting, SENR9968, "Cleanliness of Fuel System Components" and Systems Operation, Testing and Adjusting, RENR9965, "Cleanliness of Fuel System Components"for detailed information on the standards of cleanliness that must be observed during ALL work on the fuel system.

Note: Ensure that the tools are stored with the caps in place. Store the tools in a clean plastic bag.

1. Ensure that the fuel level in the fuel tank is above the level of the suction pipe in the fuel tank.

2. Inspect the fuel system thoroughly for leaks. If necessary, repair the fuel system.

3. Check all low pressure fuel lines from the fuel tank for restrictions. Replace any damaged components.

4. Install new fuel filters. Refer to Operation and Maintenance Manual, SEBU8120 and Operation and Maintenance Manual, SEBU8180 for the correct procedures.

5. Run the engine. Check if the problem has been resolved. Stop the engine. Refer to Operation and Maintenance Manual, SEBU8120 and Operation and Maintenance Manual, SEBU8180 for the correct procedure.

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Illustration 1	g01323442
Typical example

6. Remove the connection (1) from the top of the secondary fuel filter base. Insert the end of the connection into a suitable container.

7. Fit a suitable tube to the top of the secondary fuel filter base. Insert the other end of the tube into a suitable container.

8. Prime the fuel system. Refer to Operation and Maintenance Manual, SEBU8120, "Fuel System - Prime" and Operation and Maintenance Manual, SEBU8180, "Fuel System - Prime" for the correct procedure. Check that fuel is flowing from the secondary fuel filter base. If there is no flow of fuel, check the operation of the fuel priming pump. If there is still no flow of fuel, replace the secondary fuel filter base. Refer to Disassembly and Assembly, RENR9722, "Fuel Filter Base - Remove and Install - Secondary Fuel Filter" and Disassembly and Assembly, KENR6216, "Fuel Filter Base - Remove and Install - Secondary Fuel Filter" for the correct procedure.

9. Stop the engine. Refer to Operation and Maintenance Manual, SEBU8120 and Operation and Maintenance Manual, SEBU8180 for the correct procedure. Remove the suitable tube at the top of the secondary fuel filter base. Install the connection (1) to the top of the secondary fuel filter base.

10. Remove the low pressure fuel line from the inlet connection (2) of the secondary fuel filter base.

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Illustration 2	g01323443
Typical example

11. Connect Tooling (A) and (B) to the low pressure fuel line. Insert the open end of the tube into a suitable container.

12. Prime the fuel system to flush fuel through Tooling (A) and (B). This will minimize the risk of contaminating the system by introducing dirt from the service tool. Refer to Operation and Maintenance Manual, SEBU8120, "Fuel System - Prime" and Operation and Maintenance Manual, SEBU8180, "Fuel System - Prime" for the correct procedure.

13. Connect the open end of the tube to the inlet connection (2) of the secondary fuel filter base. Prime the fuel system. Refer to Operation and Maintenance Manual, SEBU8120, "Fuel System - Prime" and Operation and Maintenance Manual, SEBU8180, "Fuel System - Prime" for the correct procedure.

14. Ensure that Tooling (A) and Tooling (B) are secured and clear of rotating parts.

15. Start the engine. Refer to Operation and Maintenance Manual, SEBU8120 and Operation and Maintenance Manual, SEBU8180 for the correct procedure. Refer to steps 15.a to 15.c for the procedure for testing the fuel pressure. Refer to steps 15.d to 15.h for the procedure for testing the air in fuel.

    Note: The pressure at the fuel transfer pump should not be measured when the engine is cranked. The pressure will be low and inconsistent. The engine should still start even if transfer pressure is zero. The fuel injection pump will deliver residual fuel in the fuel injection pump and the secondary fuel filter.

    1. Run the engine at a speed of 1000 rpm. The fuel pressure should be 300 to 550 kPa (44 to 80 psi).

    2. If the fuel pressure is more than 600 kPa (87 psi), there is a problem with the pressure regulator for the fuel transfer pump. Replace the fuel transfer pump. Refer to Disassembly and Assembly, RENR9722, "Fuel Transfer Pump - Remove" and Disassembly and Assembly, KENR6216, "Fuel Transfer Pump - Remove" for the correct procedure.

    3. If the pressure is less than 300 kPa (44 psi), check for restrictions in the low pressure fuel lines between the fuel transfer pump and the secondary fuel filter base. Check for excessive air in the fuel. If no faults are found, replace the fuel transfer pump. Refer to Disassembly and Assembly, RENR9722, "Fuel Transfer Pump - Remove" and Disassembly and Assembly, KENR6216, "Fuel Transfer Pump - Remove" for the correct procedure.

    4. Run the engine high idle.

    5. Run the engine for two minutes. There should be no air in the fuel flow through the sight tube. Small bubbles that are spaced more than 2.5 cm (1.0 inch) are acceptable. Do not manipulate the connections during the test for the air in fuel.

    6. The presence of large bubbles or a continuous stream of bubbles indicates a leak before the transfer pump.

    7. Investigate potential leaks and rectify any potential leaks in the low pressure fuel system between the fuel tank and the inlet at the fuel transfer pump.

    8. Inspect the primary filter base for damaged connections. Inspect the main fuel inlet connection from the fuel tank. Ensure that all the connections are correctly installed. If necessary, replace the connections.

16. Remove Tooling (A) and (B). Reconnect the low pressure lines.