Replacing Fuel Connector Tubes In A '99 Cummins: Step-By-Step Guide

The connector tube is responsible for transferring fuel from the injection line to the fuel injector. It is recommended to replace the connector tube when replacing the injector. This is because the connector tube fits into a tapered opening in the injector and forms a metal-to-metal seal. Leakage here is a common problem that causes hard start and no-start symptoms. The connector tube nut must be torqued to 37 ft-lbs.

There are several steps to changing the fuel connector tubes. First, you must drain the diesel in the canister. Then, you can start to remove the old tubes and replace them with new ones. It is important to note that there are different types of connector tubes, so you must use the correct ones for your engine. Finally, you can fill the canister with fresh diesel and put it back on.

Injector connector tubes are responsible for transferring fuel from the injection line to the fuel injector

The injector connector tubes are a critical component in the fuel injection system of a Cummins engine. These tubes are responsible for transferring fuel from the injection line, located outside the cylinder head, to the fuel injector situated in the centre of the cylinder head. This process involves a precise metal-to-metal seal, formed by the connector tube fitting into a tapered opening within the injector.

The importance of maintaining the integrity of this fuel transfer system cannot be overstated. Leakage is a common issue, which can lead to hard start and no-start symptoms. To prevent this, it is vital to pay close attention to the torque applied to the connector tube nut, which must be set at exactly 37 ft-lbs.

Given the critical nature of this component, it is highly recommended to replace the connector tube whenever the fuel injectors are serviced. Reusing old connector tubes can lead to repeat leakage failure, potentially causing costly damage to the new injector. New connector tubes are a wise investment, offering relatively inexpensive insurance against potential issues.

When replacing the connector tubes, it is essential to use the correct tubes designed for the specific engine. For instance, for the 03-07 5.9L engines, the recommended part number is F00RJ01572, while for the 6.7L engines, the part number is 4929864. It is worth noting that reusing the tubes is possible, but it carries the risk of potential issues, and the general consensus is to replace them whenever the injectors are serviced.

It is recommended to replace the connector tube at the time of injector replacement

The connector tube is responsible for transferring fuel from the injection line at the outside of the cylinder head to the fuel injector in the centre of the cylinder head. The connector tube fits into a tapered opening in the injector and forms a metal-to-metal seal. Leakage here is a common problem, causing hard start and no-start symptoms. It is highly recommended to replace the connector tube at the time of injector replacement.

If an old connector tube is re-used, a repeat leakage failure can occur, damaging the body of the new injector. This is not a warrantable failure. New connector tubes are relatively inexpensive insurance. The torque on the connector tube nut is critical and must be 37 ft-lbs.

When replacing the connector tube, it is important to use the correct feed tubes. For the 03-07 5.9L engines, use part # F00RJ01572. Do not use the 6.7L feed tubes (part # 4929864) that superseded them, as these are made to fit and seal with the 6.7L engines. The F00RJ01572 fits and seals better with the 03-07's.

You can also purchase an injector install kit for the 03-07 5.9L engines, which contains six feed tubes, two intake horn gaskets, and one connector tube removal tool.

The connector tube fits into a tapered opening in the injector and forms a metal-to-metal seal

The connector tube is responsible for transferring fuel from the injection line to the fuel injector. The tube fits into a tapered opening in the injector, creating a metal-to-metal seal. This seal is formed by metal-to-metal wedging of the threads. To ensure a proper seal, it is critical to apply thread sealant to the connector tube before installation. This will help to reduce the chances of leakage.

The connector tube must be torqued correctly to prevent high-pressure fuel leaks. If the fitting is not tight enough, the surfaces may not seal properly, resulting in a leak. On the other hand, over-tightening the connector tube can deform the surfaces, leading to the same issue. Therefore, it is crucial to achieve the correct torque of 37 ft-lbs when installing the connector tube.

The Edge Filter within the connector tube acts as the last line of defence against contaminants in the fuel system. It pulverizes any remaining contaminants to less than ten microns in size as they pass through the tube towards the injector. However, it is important to note that the Edge Filter is not serviceable, and if it becomes clogged, the connector tube must be replaced.

Additionally, whenever the connector tube is removed or installed, the O-ring should also be replaced to maintain a proper seal. Before reassembling the fuel system, it is recommended to inspect the connector tubes and O-rings thoroughly to ensure they are in flawless condition. This proactive measure can help avoid issues such as low power or misfiring.

Torque on the connector tube nut is critical and must be 37 ft-lbs

When changing the fuel connector tubes on a 99 Cummins, torque on the connector tube nut is critical and must be 37 ft-lbs. This is because the connector tube is responsible for transferring fuel from the injection line outside the cylinder head to the fuel injector in the centre. The connector tube fits into a tapered opening in the injector, creating a metal-to-metal seal. If the torque on the connector tube nut is too high or too low, this seal may not form correctly, leading to fuel leakage. This can cause hard start and no-start symptoms.

It is highly recommended to replace the connector tube when replacing the injector. Reusing an old connector tube can cause repeat leakage failure, which can damage the body of the new injector. New connector tubes are relatively inexpensive and can prevent future issues.

When replacing the connector tube, it is important to use the correct tubes. For the 03-07 5.9L engines, use part # F00RJ01572. Do not use the 6.7L feed tubes (part # 4929864) as these are designed for the 6.7L engines and may not seal properly with the 5.9L engines.

It is also important to note that fuel lines should be considered a single-use item. While they can be reused, it is not recommended as they may not perform adequately due to metal fatigue and crush.

Reusing old connector tubes can lead to repeat leakage failure and damage to the new injector

The connector tube is responsible for transferring fuel from the injection line to the fuel injector. The connector tube fits into a tapered opening in the injector and forms a metal-to-metal seal. Leakage here is a common problem which causes hard start and no-start symptoms. Torque on the connector tube nut is critical and must be 37 ft-lbs.

It is highly recommended to replace the connector tube at the time of injector replacement. Reusing old connector tubes can lead to repeat leakage failure and damage to the new injector. This is because the tubes are a crush fit and mould to the injector. They also carry very high-pressure fuel, meaning that metal fatigue and crush will render them inadequate for reuse. The bevel on the tube and injector is also slightly different, which will lead to sealing issues.

New connector tubes are relatively inexpensive. While they can be reused, doing so is a chance not worth taking. The cost of a tow and/or troubleshooting issues or fixing the problem can easily exceed the cost of the tubes.

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