Note: In this article I will describe the process of installing an additional A/C compressor as on-board air compressor. In order to keep things simple- the original A/C

compressor will be referred as “A/C compressor“, and the on-board air compressor will be referred as “Air compressor“.

I looked for a solution for a fast air compressor, which will be able to operate the ARB air locks as well as fast inflation of the wheels.
One option was to buy a good electric compressor (such as Thomas) and make some changes so it will be able to operate the ARB air-locks.
The other option was to take an old A/C compressor and use it as a fast-air compressor. – The 2nd option was much more complicated, but definitely faster and

stronger compressor.
In this case I had to find a proper place to place the additional air compressor without moving out the A/C compressor.
It looks simple, but after having a look under the defender TDI-300 hood, you can see that there is no so much room.
Pictures:
In this picture you can see the original stand to the A/C compressor next to the just-built new stand that supports two compressors:

After connecting the base of the stand to the engine block with the four screws that were holding the original stand, we were able to determine the exact location of the compressors. After locating the exact spot of the compressor – using Arc Welder and attaching it to the right place.
The air compressor was located closer to the engine head, in the same level the A/C compressor was mounted before the change. The A/C compressor was lifted a little in order not to hit the injection pump.

In this picture you can see the cylinder attached to the A/C compressor, just before welding it into the base:

In the following picture we removed the Air compressor in order to weld the cylinder to the base properly:

This picture shows the final location of the compressors after the installation:

On the right side you can see the Air compressor connections- Air intake from the engine breather:

The output compressed air runs to an airline filter, that separates the water and oil from the air. passing one-way valve – to the air-tank. The one-way valve is required in order to avoid pressure loss from the air compressor:

Air tank in located under the vehicle, just below the right side chair, from there air line goes to the box under the passenger side. You can see the pressure safety valve connected to the air tank:

In this box we installed the pressostat- the pressure sensor that controls the compressor. It is connected to a “T” – where in one side there is a pressure regulator- which goes to the Arb front and rear solenoid. The other side of the “T” is connected to a quick disconnect – where we can use tools and wheel inflation.

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