Repair 7

The orifice tube on a Ford truck is a hard debris filter for the air conditioning system. If a component in the system fails, the orifice tube prevents the debris from the failure from spreading throughout the system.

Location

The orifice tube resides in the liquid line between the receiver/dryer and the evaporator. The liquid line brings rigerant into the evaporator, the component that removes heat from the air in the passenger compartment.

Purpose

The rigerant flows through the AC system, outward from the AC compressor, through the manifold hose, condenser, receiver/dryer and evaporator before returning to the compressor.

Purpose

When performing a full AC system inspection, after evacuating the system with a rigerant service machine, remove the orifice tube and visually inspect it. If you note any signs of debris in the line, the AC compressor is most likely coming apart inside and requires replacement.

The exhaust gas recirculation (EGR) system is used in car engines to reduce exhaust emissions. Though EGR problems are often blamed on the EGR valve, its the tube that can become clogged and will require cleaning.

How It Works

The EGR system works by allowing a small amount of exhaust to return to the combustion chamber. The gases cause a reduction in ignition temperature, which prevents the formation of NOx and other pollutants. The EGR system uses a valve that opens and closes to maintain the proper temperature.

Components

The primary component of the EGR system is the valve. Valves can be controlled either by vacuum pressure or electronics. When the gas is needed to cool combustion, the valve is opened. The exhaust gases move through the open valve and pass through a small tube or channel back to the intake manifold.

Tube Cleaning

The exhaust gases often carry small particles. These particles can become deposited inside the EGR valve or tube and clog the system causing it to fail. EGR tube cleaning simply ers to the process of cleaning this sediment from the tube. Most sediment will accumulate in the tube near the valve and can be removed with a small wire. Larger deposits will require the manifold to be removed for cleaning.

A Ford Windstars air conditioning orifice tube is also know as an expansion tube. The component contains a filter and it screens out particles, such as dirt, grit and metal shavings, in the air from within high-pressure line. The orifice tube should be removed and replaced after all refrigerant has been discharged from the air conditioning system. The tube is located in the Windstars engine compartment.

Instructions

1

Release the Windstars hood latch. Open and secure the hood.

2

Look toward the center of the engine compartment and locate two sets of aluminum pipes. The larger of the two pipes is the low-pressure line. The thinner is the high-pressure line.

3

Follow the high-pressure line to the evaporator. At the end the line is the orifice tube.

Cars no longer use tubes. All car tires are tubeless. However, if the spare tire in your trunk wont hold air, it might mean that the wheel itself is defective or has a small leak and air is leaking out through the rim. If this is the case, you can have a tube installed in the tire for limited use. There are tubes of all sizes and they are very forgiving if they are close to the right size.

Instructions

1

Take the spare tire out of the trunk. Inspect the side of the tire.

2

Look for the distinction marked either "P" for passenger tire, or a "T" meaning temporary service. The next numbers are 225/50. These are common to all tires, so dont worry about these numbers.

3

Look after the numbers 225/50 for the number 13, 14, 15 or 16. This is the size of the wheel. It might be any of these.

4

Purchase a tube coordinating it with the letter and the wheel size. Look on the side of the package for the sizes. Some tubes actually are interchangeable, and they will be clearly marked if they are.