Post by Admin on Oct 26, 2007 11:37:57 GMT -4
How to use a AC compressor as a engine driven air compressor.
The most common compressor for this type of setup is the York-style compressor. It can be found on Ford, Volvo, AMC, IH, and Oldsmobile vehicles from the late 70's to the early 80's.
Why a York? The compressors found on most vehicles with A/C are lubricated internally, by the freon in the system. For pumping air, you would have to have an external oiler to keep the compressor lubricated, and a filter to remove the oil from the output of the compressor. With a York, this is not necessary. It has it's own internal reservoir for oil, making it a much better choice for pumping air. However, there are many variables when considering which style of York to use. There are three different displacements or strokes available, as well as many different types of hose connections.
Of the three different stroke models, the long stroke York is the most desirable. The longer the stroke, the bigger volume of air pumped per minute. The easiest way to determine the output or stroke of the compressor is to look at the crankshaft. To get to the crankshaft, you must remove the pulley. This can be done by removing the bolt and washer holding the pulley on, and running a 5/8" coarse thread bolt in to force the pulley off. All models have a flat end on the crankshaft; the edges of the crankshaft are what's important. A beveled edge on the end is the short stroke. If it has a sharp corner, but is grooved for a retaining clip, it's a medium stroke. And if it is a sharp corner without any grooves, it's a long stroke. If the compressor still has the original Motorcraft metal tag bolted to it, you can use that for reference also. It will have a series of five numbers/letters. The last three are the displacement, and direction. Of those last three digits, the last letter is the output direction and the other two are the stroke. The three stroke numbers are: 10 = long stroke, 09 = medium stroke, 07 = short stroke. The Discharge Direction letters are: L = left, R = right. So if it's a **09R, then it's a medium stroke with a right side discharge.
But, the tag is not the best way to identify which model is on the vehicle, because it's common to replace the tag when the compressor is serviced. The single best way to identify the model is to remove the pulley.
Of the vehicles that used York compressors, the long stroke model is most common in late 70's to early 80's Volvos. There is not much information about which models were common on AMC's or Fords, but most people asked seem to agree that most Volvos were usually long stroke. The hose connectors can also be a factor when looking for the right compressor. Volvo and AMC-style hose connectors, run horizontally across the top of the compressor. Ford-style connectors stick straight up out of the top of the compressor and then connect to the A/C system. This can make the overall height of the unit a little taller. The different connector styles are interchangeable, but finding fittings for the factory A/C connectors is difficult, because the threads don't match common pipe fittings. Fortunately, onboardair.com makes custom flange fittings that use a common 1/2"npt, and they are a direct replacement for the factory fittings. There are also several different types of heads found on the York compressor, but the two most common are the Flange style or the tube "0" or rotolock style.
There are also several different variations of pulley/clutch assemblies found on York compressors. Depending on your particular application, it may be beneficial to get a few different compressors to mix and match the pulleys.
There are two things to test for: 1. If the clutch works, and 2. If the compressor pumps air. To test the clutch, look for a single wire coming out of the compressor. This is the wire that is normally connected to the A/C switch on the vehicle, and controls the clutch/pulley assembly. When the wire receives power, it "locks" the clutch, and turns the crankshaft on the compressor. The outer part of the pulley assembly is always turning when the engine is running, and it should spin freely. The inner part of the pulley is what actually makes the compressor turn. To test the clutch, ground the compressor, and touch the single wire to a positive battery terminal. You should hear a "click" when you apply power to the wire. This "click" is the outer part of the pulley, locking to the inner part on the crankshaft. You should be able to turn the pulley with it locked and be able to hear air being pumped. It should also be harder to turn because of this. Also, when you remove the wire, you should hear a "click" again, and the outer part of the pulley should disengage and spin freely again. It is also a good idea to plug one of the hoses with your thumb and turn the crankshaft (inner part of the pulley) with or without the clutch being engaged. Depending on which direction it's turned, it should either suck or blow air against your thumb. It's a good idea to turn it both ways just to be sure it works. If the compressor fails either of these two tests, it has internal damage, or a bad clutch. New clutches aren't cheap, so be sure to get one that works.
How do I mount it? This is probably the hardest part of the whole on-board air project. As of now, there are no brackets mass-produced to mount a York on a Chevy V8. You will have to make one, or find someone to make it. The compressor MUST be mounted in the vertical position or as close to vertical as possible. If not, the oil will spill out of the reservoir and get in the air lines. If your engine uses serpentine belts, onboardair.com also has a serpentine/v-belt combination pulley for alternators that will allow you to run a v-belt to the compressor. It might work with a Chevy alternator, but I'm not sure.
Keeping the compressor lubricated. The quickest way to burn up a York is to let it run out of oil. Since it's not pumping freon anymore, you have to keep it oiled. The compressor has an oil fill/check hole on the side about half way up. It has a capacity of about 12 ounces.
The most common compressor for this type of setup is the York-style compressor. It can be found on Ford, Volvo, AMC, IH, and Oldsmobile vehicles from the late 70's to the early 80's.
Why a York? The compressors found on most vehicles with A/C are lubricated internally, by the freon in the system. For pumping air, you would have to have an external oiler to keep the compressor lubricated, and a filter to remove the oil from the output of the compressor. With a York, this is not necessary. It has it's own internal reservoir for oil, making it a much better choice for pumping air. However, there are many variables when considering which style of York to use. There are three different displacements or strokes available, as well as many different types of hose connections.
Of the three different stroke models, the long stroke York is the most desirable. The longer the stroke, the bigger volume of air pumped per minute. The easiest way to determine the output or stroke of the compressor is to look at the crankshaft. To get to the crankshaft, you must remove the pulley. This can be done by removing the bolt and washer holding the pulley on, and running a 5/8" coarse thread bolt in to force the pulley off. All models have a flat end on the crankshaft; the edges of the crankshaft are what's important. A beveled edge on the end is the short stroke. If it has a sharp corner, but is grooved for a retaining clip, it's a medium stroke. And if it is a sharp corner without any grooves, it's a long stroke. If the compressor still has the original Motorcraft metal tag bolted to it, you can use that for reference also. It will have a series of five numbers/letters. The last three are the displacement, and direction. Of those last three digits, the last letter is the output direction and the other two are the stroke. The three stroke numbers are: 10 = long stroke, 09 = medium stroke, 07 = short stroke. The Discharge Direction letters are: L = left, R = right. So if it's a **09R, then it's a medium stroke with a right side discharge.
But, the tag is not the best way to identify which model is on the vehicle, because it's common to replace the tag when the compressor is serviced. The single best way to identify the model is to remove the pulley.
Of the vehicles that used York compressors, the long stroke model is most common in late 70's to early 80's Volvos. There is not much information about which models were common on AMC's or Fords, but most people asked seem to agree that most Volvos were usually long stroke. The hose connectors can also be a factor when looking for the right compressor. Volvo and AMC-style hose connectors, run horizontally across the top of the compressor. Ford-style connectors stick straight up out of the top of the compressor and then connect to the A/C system. This can make the overall height of the unit a little taller. The different connector styles are interchangeable, but finding fittings for the factory A/C connectors is difficult, because the threads don't match common pipe fittings. Fortunately, onboardair.com makes custom flange fittings that use a common 1/2"npt, and they are a direct replacement for the factory fittings. There are also several different types of heads found on the York compressor, but the two most common are the Flange style or the tube "0" or rotolock style.
There are also several different variations of pulley/clutch assemblies found on York compressors. Depending on your particular application, it may be beneficial to get a few different compressors to mix and match the pulleys.
There are two things to test for: 1. If the clutch works, and 2. If the compressor pumps air. To test the clutch, look for a single wire coming out of the compressor. This is the wire that is normally connected to the A/C switch on the vehicle, and controls the clutch/pulley assembly. When the wire receives power, it "locks" the clutch, and turns the crankshaft on the compressor. The outer part of the pulley assembly is always turning when the engine is running, and it should spin freely. The inner part of the pulley is what actually makes the compressor turn. To test the clutch, ground the compressor, and touch the single wire to a positive battery terminal. You should hear a "click" when you apply power to the wire. This "click" is the outer part of the pulley, locking to the inner part on the crankshaft. You should be able to turn the pulley with it locked and be able to hear air being pumped. It should also be harder to turn because of this. Also, when you remove the wire, you should hear a "click" again, and the outer part of the pulley should disengage and spin freely again. It is also a good idea to plug one of the hoses with your thumb and turn the crankshaft (inner part of the pulley) with or without the clutch being engaged. Depending on which direction it's turned, it should either suck or blow air against your thumb. It's a good idea to turn it both ways just to be sure it works. If the compressor fails either of these two tests, it has internal damage, or a bad clutch. New clutches aren't cheap, so be sure to get one that works.
How do I mount it? This is probably the hardest part of the whole on-board air project. As of now, there are no brackets mass-produced to mount a York on a Chevy V8. You will have to make one, or find someone to make it. The compressor MUST be mounted in the vertical position or as close to vertical as possible. If not, the oil will spill out of the reservoir and get in the air lines. If your engine uses serpentine belts, onboardair.com also has a serpentine/v-belt combination pulley for alternators that will allow you to run a v-belt to the compressor. It might work with a Chevy alternator, but I'm not sure.
Keeping the compressor lubricated. The quickest way to burn up a York is to let it run out of oil. Since it's not pumping freon anymore, you have to keep it oiled. The compressor has an oil fill/check hole on the side about half way up. It has a capacity of about 12 ounces.