4.3LXJ
05-05-2010, 02:16 PM
i would like to know how to make the air compressor with the ac compressor.
I had a request on how to make an AC compressor into an air compressor.
Most of us have a Sanden compressor in our Jeeps. This is a very popular and proven compressor that has 5 horizontal pistons driven by wobbling crank shaft with a clutch on it. At idle, it will fill a tire in about a minute or less. At about 2,000 rpms it will cycle while filling a tire and run any air tool you can name. They are rated at 12CFM @100 psi and will pump 400 psi without a problem. But they have one weakness, lubrication. They are designed to have refrigerant mixed with oil pumping through them. There are two things you can do. One is to run an air tool oiler on the intake side. The other is do what a friend of mine has done for the last 10 years on his trail XJ, pour a little vegetable oil in the intake before use. I have a third option that is uncommon, I run oil in the crank case and recover it and return it to the crank case.
I don't have pics of building the bracket that holds my OBA. I did it before logging on to forums so I didn't think it important at the time. But here is the general things you need to do.
You start with a compressor of course.
http://i649.photobucket.com/albums/uu215/warriorsuspension/IMG_0075.jpg
The one on the left is the OBA compressor. At the back of the compressor is the intake/output manifold. On the right side is the intake, the larger of the two tubes. This needs to have a clean source. I use a power brake hose off the air horn of my intake so it gets filtered air. Most people with a 4.0 will use a small lawn mower filter available at NAPA or other real auto parts stores. Next is the output side on the left. I used the ends of AC hoses for both. But this is the pressure side and needs good hose. I have a quick disconnect fitting on this so I can remove it to remove my air intake assembly in a couple of minutes. To make this set up, I just silver soldered the fitting on to the tube. Make sure you start with a steel hose end for this and use the AC O rings to seal everything tight. I used silver solder because it will stick to steel and also brass alloys like the quick disconnect is made of. If you have never used it before, It is half way between brazing and gas welding. You heat everything up red hot and apply after cleaning. It is used extensively in the AC industry. The quick disconnect fitting on the right is for my oil return and I will address that later.
The next thing needed is controls for the compressor.
http://i649.photobucket.com/albums/uu215/warriorsuspension/IMG_0074.jpg
The quick disconnect on the left is the pressure intake for this assembly. I got most of this stuff from Kilby Enterprises. The first thing behind the disconnect is a check valve. This keeps the pressurized air from going back through the compressor and in my case forcing crank case oil out of it. It is a necessary item if you are going to use oil in the case and also if you are going to use the system for more than filling tires, such as for air lockers. The next item after the elbow is an oil separator. This is recommended so you do not get oil in things like tires or mix oil in your differentials.
The next item to the right is the manifold that has two necessary items. First is the pop off valve. This is important because it needs to vent excess pressure. The compressor will pump 400 psi and not blink. That will blow some things like hoses and tires. The other is the pressure switch, which turns the compressor on and off by engaging an disengaging the clutch. Mine is set for 140 psi. The next item is not necessary unless you have air lockers, pressure regulator. Air lockers are supposed to run at 100 psi, less than the 140 psi the system will be operating at. The last is the ARB solenoid valves. Can you guess what is in my future?
The last item is not pictured and is in the back of the rig. A 2 gal air tank. This is a necessary item so that your compressor does not short cycle every second and can be mounted anywhere, or can be even a tube bumper that is sealed.
I had a request on how to make an AC compressor into an air compressor.
Most of us have a Sanden compressor in our Jeeps. This is a very popular and proven compressor that has 5 horizontal pistons driven by wobbling crank shaft with a clutch on it. At idle, it will fill a tire in about a minute or less. At about 2,000 rpms it will cycle while filling a tire and run any air tool you can name. They are rated at 12CFM @100 psi and will pump 400 psi without a problem. But they have one weakness, lubrication. They are designed to have refrigerant mixed with oil pumping through them. There are two things you can do. One is to run an air tool oiler on the intake side. The other is do what a friend of mine has done for the last 10 years on his trail XJ, pour a little vegetable oil in the intake before use. I have a third option that is uncommon, I run oil in the crank case and recover it and return it to the crank case.
I don't have pics of building the bracket that holds my OBA. I did it before logging on to forums so I didn't think it important at the time. But here is the general things you need to do.
You start with a compressor of course.
http://i649.photobucket.com/albums/uu215/warriorsuspension/IMG_0075.jpg
The one on the left is the OBA compressor. At the back of the compressor is the intake/output manifold. On the right side is the intake, the larger of the two tubes. This needs to have a clean source. I use a power brake hose off the air horn of my intake so it gets filtered air. Most people with a 4.0 will use a small lawn mower filter available at NAPA or other real auto parts stores. Next is the output side on the left. I used the ends of AC hoses for both. But this is the pressure side and needs good hose. I have a quick disconnect fitting on this so I can remove it to remove my air intake assembly in a couple of minutes. To make this set up, I just silver soldered the fitting on to the tube. Make sure you start with a steel hose end for this and use the AC O rings to seal everything tight. I used silver solder because it will stick to steel and also brass alloys like the quick disconnect is made of. If you have never used it before, It is half way between brazing and gas welding. You heat everything up red hot and apply after cleaning. It is used extensively in the AC industry. The quick disconnect fitting on the right is for my oil return and I will address that later.
The next thing needed is controls for the compressor.
http://i649.photobucket.com/albums/uu215/warriorsuspension/IMG_0074.jpg
The quick disconnect on the left is the pressure intake for this assembly. I got most of this stuff from Kilby Enterprises. The first thing behind the disconnect is a check valve. This keeps the pressurized air from going back through the compressor and in my case forcing crank case oil out of it. It is a necessary item if you are going to use oil in the case and also if you are going to use the system for more than filling tires, such as for air lockers. The next item after the elbow is an oil separator. This is recommended so you do not get oil in things like tires or mix oil in your differentials.
The next item to the right is the manifold that has two necessary items. First is the pop off valve. This is important because it needs to vent excess pressure. The compressor will pump 400 psi and not blink. That will blow some things like hoses and tires. The other is the pressure switch, which turns the compressor on and off by engaging an disengaging the clutch. Mine is set for 140 psi. The next item is not necessary unless you have air lockers, pressure regulator. Air lockers are supposed to run at 100 psi, less than the 140 psi the system will be operating at. The last is the ARB solenoid valves. Can you guess what is in my future?
The last item is not pictured and is in the back of the rig. A 2 gal air tank. This is a necessary item so that your compressor does not short cycle every second and can be mounted anywhere, or can be even a tube bumper that is sealed.