I bought a 91 mustang the a/c worked for a little while and then stopped working. Ac clutch wont turn on I know there a low freon shut off. I tried putting freon in the low side and the can reading was way high in the red. cant remember the exact psi. Clutch wont engage either. I'm thinking I need a new compressor any thoughts?
A/c PROBLEM think it maybe a compressor
- Thread starter Huff890
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Need to put a set of guages on there and see what your actual pressures are.
If yo pull the plug off the acumulator on the passenger firewall (football sized tank) and jump the harness plug out, the compressor should come on.
If yo pull the plug off the acumulator on the passenger firewall (football sized tank) and jump the harness plug out, the compressor should come on.
- Mar 2, 2015
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If the compressor clutch isn't engaging you can just replace the clutch assembly and you wont have to buy a bunch of freon or vacuum down the system.
That switch works two ways...if there's too much freon it won't cut the compressor on...and if theres too little it won't come on. You need to take a piece of wire....with the car off but key and ac on, unplug the switch and jump the connector...pink wire to green. The compressor clutch should click and move in and out as you tap the wire in the connector. If that works then report back here.
Basically, if the clutch is working then there are two other options....either too much or little freon...or the switch is bad.
Using that can stuff the car has to be running and ac on max to work. If the car is off when you put it in it will put too much pressure. The only way to fix that is to release pressure and start again. There is a huge fine for putting that stuff in the atmosphere. ( if someone sees and complains to OSHA )
That switch works two ways...if there's too much freon it won't cut the compressor on...and if theres too little it won't come on. You need to take a piece of wire....with the car off but key and ac on, unplug the switch and jump the connector...pink wire to green. The compressor clutch should click and move in and out as you tap the wire in the connector. If that works then report back here.
Basically, if the clutch is working then there are two other options....either too much or little freon...or the switch is bad.
Using that can stuff the car has to be running and ac on max to work. If the car is off when you put it in it will put too much pressure. The only way to fix that is to release pressure and start again. There is a huge fine for putting that stuff in the atmosphere. ( if someone sees and complains to OSHA )
First, OSHA don't give a rats red bunion hole about releasing cfc's (or whatever it's classification is) into the atmosphere unless someone on the job is injured. Go ahead and try to report someone for releasing that stuff, it's a joke, but that is not what we are here to talk about.
As stated above, too much pressure is as bad as not enough. Jumping the limiter switch will force the compressor to pump, I know of several people that have added a can of Freeze to it and it worked for a very long time but it contaminates the system and can mess up the filters on a commercial recovery machine.
Most ac/repair shops will check your system for free.
As stated above, too much pressure is as bad as not enough. Jumping the limiter switch will force the compressor to pump, I know of several people that have added a can of Freeze to it and it worked for a very long time but it contaminates the system and can mess up the filters on a commercial recovery machine.
Most ac/repair shops will check your system for free.
I think he meant the EPA. They might care if a A/C repair shop is performing work by just venting the old refrigerant out vs reclaiming it. I doubt they will care about Joe Blow fixing his AC in his garage even if they do frown upon that. Also...your neighbors would really have to hate you to report you for that if they even knew what you were doing.
I do remember from the EPA609 test (so i could buy R-12) that they frown upon any A/C work done if the system has a known leak. So no pulling up to Autozone and dumping a can of R-134a in your leaky system to try and get another 2-3 months out of it.
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Here's some A/C Recharge help...
Here's some more help in the A/C arena...
Currently, I am running Enviro-Safe R12 substitute, and it works very well. eBay has 3 can package for $25 + shipping. It does not require any vacuuming or purging of the system, and is a real aid to the DIY guy looking to save some $$. The warning say it is flammable, but so is gasoline...
no matter what refrigerant you use, you will need to replace the accumulator/dryer; cost is about $55-$95
Try eBay for some R12, it is running $20-$30 a can. You need 3 each 12 oz. cans and 6-8 oz. of R12 compatible mineral oil. The R12 compatible oil is like $20 a quart when you can find it. You may be able to find a combination can of R12 and oil together which may be cheaper than buying a quart of oil..
It is illegal for a company to sell any refrigerant other than R134 to a person who does not have an EPA 608 or 609 certification. That includes Freeze 12. However, individual sellers like those on eBay and, not affiliated with a store often do not ask for any certification information, they just want prompt payment.
See http://www.epa.gov/Ozone/title6/608/overlap.html for more details
R134a Air Conditioner Conversion and recharge instructions
Revised 14-Jul-2013 to add Low Pressure Cutout Switch adjustments for R134 & Freeze 12
Color Legend:
R134 specific items and instructions are in red text
Freeze 12 specific items instructions are in orange text
Note: R12 is available on eBay. Use the Freeze 12 instructions except use the R12 36 oz refrigerant charge with R12 refrigerant
Items and instructions common to both R134 and Freeze 12 are in black text
Tools and materials you will need:
Gauge set for recharging = $20-$120 – check out the pawn shops for a bargain before you pay retail.
See Harbor Freight Tools for an inexpensive gauge set.
Vacuum pump – I use an old refrigerator compressor = $20- $40 at used appliance stores, or go to the Dump and get one for free. Be sure to have some R12 compatible oil handy to keep it lubed up properly.
O ring seal kit = $8.
Replacement accumulator/dryer assembly with hose $55-$75
Alternative refrigerant – Freeze 12 – it will allow you to skip flushing the system and reuse the original accumulator/dryer under certain conditions:
1.) If the A/C system has not been open to air for more than an hour or so.
2.) Or if it hasn’t out of refrigerant for more than 5-7 days and the system is till sealed up with no open or disconnected lines. You need to be able to hear the hiss when depress the valve core in either one of the service ports. That tells you that there is still pressure in the system, which keeps out moisture and contaminants.
If either of the above is not true, you must replace the accumulator/dryer assembly.
Freeze 12 refrigerant: $15-$16 per 12 Oz can on eBay. Get 3 cans, 2 for the initial charge and 1 spare for a top off charge.
Use R12 compatible mineral oil, 6-8 Oz. This may be difficult to find or expensive (~$20 a quart). Sometimes eBay will have the oil/R12 combination cans, which have about 4 oz. R12 and 2 oz. oil in them. If you go this route, add the R12/oil charge first, then add the cans of R12.
Do not use PAG oil in a Freeze 12 system without flushing it first.
Freeze 12 refrigerant charge= 26-28 Oz plus 6-8 Oz R12 mineral oil on an empty system. A recharge may only require 2-4 OZ of R12 mineral oil if you only replaced a line, hose or seals.
A/C systems that have had a compressor failure must be flushed. Failure to do so will result in the floating trash left behind from the compressor failure destroying the replacement compressor.
R134a = $11-$16 a can – takes 2 cans.
R134a PAG or Ester compatible oil = $7-$12 for an 8 oz bottle .
Pump to force cleaning fluid through the system $20-$50 (may use compressed air to do the same thing).
R134a charging adapter = $13 (I cut mine up to use it with the R12 gauge set that I have had for a long time).
Plastic tools to disconnect refrigerant lines - 1/2" & 5/8" = $4 each.
Flushing agent - Discount Auto Parts has some flushing solvent in a 1 gallon plastic bottle - try that first. Or use Mineral spirits = $4-$5 a gallon, tetrachloroethylene =$5-$10 a gallon, takes 2 gallons of either one.
Miscellaneous hoses and fittings to adapt the flushing pump to the system, and the R134a adapter to the R12 gauge set = $15.
R134 Refrigerant charge is 26-28 Oz plus 6-8 Oz of PAG 100 oil.
R134 Conversion Instructions:
I did a R134a conversion on my 89GT, and used all stock parts. You will need to replace the dryer/receiver (about $75 if you get the one with the hose made as part of the unit), and should replace all of the rubber "O" ring seals as well. You will need to drain all of the oil out of the compressor and replace it with new R134a compatible oil.
R134 instructions (skip this if you use Freeze 12)
Keep in mind that to fulfill the requirements of the EPA, you are required by law to recover any refrigerant that still remains in the system. How (or wither or not) you accomplish this is up to you. Connect the charging gauge hoses to the service ports on the A/C (red gauge = high pressure, blue gauge = low pressure) and open the valves on the gauges to dump the remaining refrigerant (if any) into your "Freon recovery system", whatever it may be. Disconnect the charging gauges since you are finished with them until you are ready to fill the system with R134a. Next comes the nasty part – in order to get all the old oil out of the system, you will need to flush it with special flushing solvent, or mineral spirits (ok) or tetrachloroethylene (better, but may be hard to get). If you leave the old oil in place it will congeal and reduce the heat transfer in the condenser and evaporator (read that it won’t cool good) and possibly damage the compressor.
Disconnect the compressor and remove it from its mount to flush it with cleaning solvent. Pour about a cup of solvent into the suction port and turn the compressor center hub about 10 turns while shaking the compressor to move the solvent around inside the compressor sump. Drain the flushing solvent out and continue to turn the center hub by hand to force out any remaining solvent. Then fill it with oil: add about 6-8 oz of the new oil to the compressor large suction fitting. Turn the compressor center hub about 20 turns as you turn the compressor face up and face down to distribute the new oil inside the compressor. Catch and replace any oil that comes out of the compressor.
Connect the pump (I had an electric sump pump I bought for $20) to the hose from the high-pressure side of the compressor. Alternately, you could use compressed air to force the cleaning fluid through the system. I didn’t like to do this since compressed air has lots of moisture in it, which is death to A/C systems. Pump the cleaning fluid through the system and let it come out the hose that was attached to the old dryer/receiver. I used 2 gallons of mineral spirits and pumped it all through the condenser and evaporator. The expansion valve is located near the firewall in the high-pressure line of the evaporator, and may cause the cleaning fluid to trickle through the lines at a very slow pace. You may want to pump cleaning fluid through the evaporator and condenser separately to speed up the process.
All refrigerant types
Next comes the changing of all the old "O" rings so that the chances for leaks is minimized. The new R134 compatible O rings are green colored, so be sure that the replacement O rings are green. Use the plastic connector tools to separate the lines, place the extended collar part of the tool so that it faces the large part of the connector and push inwards: this expands the spring so that you can pull the tube apart. You may need a helper to push on the tool while you pull on the tubes to separate them. Install the new "O" rings: be sure to coat them with new oil when you put them in. Install the new dryer/receiver, refrigerant service port adapter on the compressor, add about more 4oz of oil to high pressure line and tighten up all the lines. You may have to add more oil when you do a system that has been flushed or new R12 installation. The total oil charge should be 6-8 oz. for all types of refrigerants. Close the hood, start the engine, let everything get warm under the hood, but don’t add the refrigerant or turn the A/C on. Connect the charging gauge hoses to the service ports on the A/C (red gauge = high pressure, blue gauge = low pressure) and open both valves, then connect the center hose to the vacuum pump. The purpose of this exercise is to heat up the system so that when you vacuum it all down (yes, you will need a vacuum pump- mine is an old refrigerator compressor), that all the air, vapor and moisture from the cleaning fluid vaporizes and is removed from the system. Vacuum it down for about 30 minutes, this should give you about 28" of vacuum or more inside the A/C system. I have a vacuum gauge "T" connected into the vacuum pump line so that I can accurately watch the vacuuming process. This is a good time to take a soda and sandwich break since it doesn’t go faster if you watch it.
the R134a service fittings on the system: the red goes on the high side and the blue on the low side. This will help others identify that a R134a conversion has been done on the system.
Typical low pressure side R134 coupling
Typical high pressure side R134 coupling
Charging instructions for all refrigerant types:
Remove the electrical connector from the dryer/receiver and jumper the two connections inside the wiring harness side of the connector together: this allows the compressor to engage in spite of low pressure/no gas in the system. Close both charging gauge valves, and then disconnect the center hose of the charging gauges from the vacuum pump and connect it to the refrigerant can tapper. Put the refrigerant can in the can tapper and screw it down with the can tapper valve closed, then open the valve. Loosen the hose at the center connection of the charging gauge set until the refrigerant squirts out: this purges the line of air and moisture. The refrigerant is added through the low pressure side of the system, so open the low pressure gauge valve to add the refrigerant. Start the car and take note of the idle speed, then set the idle speed up to about 1200-1500 rpm, and turn the A/C on inside and set the fan speed on high. Watch for the pressure on the low side to drop off as you are filling, and the refrigerant can will get warm and stay warm. This tells you the current can is empty and needs to be changed for a fresh one. Before you disconnect the can, be sure to close the valve on the refrigerant can tapper.
Watch the high side pressure on the charging gages and regulate the adding of gas to keep the high side pressure under 350 psi. You will probably need a fan in front of the car to keep the readings below 350 psi. I had to put the refrigerant can in hot water while I was charging the system with it, or else the can got so cold that it quit flowing. Use caution when you do this so that you don’t get water in the charging adapter when you change the cans.
R12 Pressures when charging is complete
When you have added the 32-36 oz. of gas, the high side will read about 250-300 psi and low side about 28-38 psi. No adjustments need to be made to the low pressure cutout switch.
Freeze 12& R134 Pressures when charging is complete.
When you have added the 24-28 oz. of gas, the high side will read about 250-300 psi and low side about 18-28 psi.
Freeze 12 & R134 Low pressure cutout switch adjustment.
The low pressure cutout switches are adjustable. They should be set with the low limit about 18-21 PSI, the stock setting is about 25 PSI. Remove the wiring connector and there is a screw slot in between the connector pins. Turning it clockwise increases the trip pressure where it cuts off and counterclockwise decreases the trip pressure. I believe that each 1/4 turn counterclockwise lowers the cutoff pressure by 1 PSI.
After Charging refrigerant instructions, all refrigerant types
Turn the idle speed back to where it was, turn the A/C off, disconnect the charging gauges, and re-install all the caps on the service ports. Remove the jumper from the low pressure switch harness and plug it back on the switch connectors.
R134 only
Then put the R134a Service Sticker on, secure all the loose wiring on the system and you are done.
The typical sticker looks like this, yours may be different.
I hope it cools good, mine doesn’t get quite as cold as it used to driving around town.
Thanks go to WWW.ACKITS.COM for some of the graphics.
Check out their website for parts and the Auto AC Forum.
The above technical note is for informational purposes only, and the end user is responsible for any damages or injury. The end user bears all responsibility for proper recovery/disposal of any R12 refrigerant.
I have EPA 608 and EPA 609 MVAC certification. And yes, you can shortcut the process, but there are negative factors if you do. Sooner or later, something will cease to function like it should. Shoddy work is a time bomb ticking away, waiting to explode.
Here's some more help in the A/C arena...
Currently, I am running Enviro-Safe R12 substitute, and it works very well. eBay has 3 can package for $25 + shipping. It does not require any vacuuming or purging of the system, and is a real aid to the DIY guy looking to save some $$. The warning say it is flammable, but so is gasoline...
no matter what refrigerant you use, you will need to replace the accumulator/dryer; cost is about $55-$95
Try eBay for some R12, it is running $20-$30 a can. You need 3 each 12 oz. cans and 6-8 oz. of R12 compatible mineral oil. The R12 compatible oil is like $20 a quart when you can find it. You may be able to find a combination can of R12 and oil together which may be cheaper than buying a quart of oil..
It is illegal for a company to sell any refrigerant other than R134 to a person who does not have an EPA 608 or 609 certification. That includes Freeze 12. However, individual sellers like those on eBay and, not affiliated with a store often do not ask for any certification information, they just want prompt payment.
See http://www.epa.gov/Ozone/title6/608/overlap.html for more details
R134a Air Conditioner Conversion and recharge instructions
Revised 14-Jul-2013 to add Low Pressure Cutout Switch adjustments for R134 & Freeze 12
Color Legend:
R134 specific items and instructions are in red text
Freeze 12 specific items instructions are in orange text
Note: R12 is available on eBay. Use the Freeze 12 instructions except use the R12 36 oz refrigerant charge with R12 refrigerant
Items and instructions common to both R134 and Freeze 12 are in black text
Tools and materials you will need:
Gauge set for recharging = $20-$120 – check out the pawn shops for a bargain before you pay retail.
See Harbor Freight Tools for an inexpensive gauge set.
Vacuum pump – I use an old refrigerator compressor = $20- $40 at used appliance stores, or go to the Dump and get one for free. Be sure to have some R12 compatible oil handy to keep it lubed up properly.
O ring seal kit = $8.
Replacement accumulator/dryer assembly with hose $55-$75
Alternative refrigerant – Freeze 12 – it will allow you to skip flushing the system and reuse the original accumulator/dryer under certain conditions:
1.) If the A/C system has not been open to air for more than an hour or so.
2.) Or if it hasn’t out of refrigerant for more than 5-7 days and the system is till sealed up with no open or disconnected lines. You need to be able to hear the hiss when depress the valve core in either one of the service ports. That tells you that there is still pressure in the system, which keeps out moisture and contaminants.
If either of the above is not true, you must replace the accumulator/dryer assembly.
Freeze 12 refrigerant: $15-$16 per 12 Oz can on eBay. Get 3 cans, 2 for the initial charge and 1 spare for a top off charge.
Use R12 compatible mineral oil, 6-8 Oz. This may be difficult to find or expensive (~$20 a quart). Sometimes eBay will have the oil/R12 combination cans, which have about 4 oz. R12 and 2 oz. oil in them. If you go this route, add the R12/oil charge first, then add the cans of R12.
Do not use PAG oil in a Freeze 12 system without flushing it first.
Freeze 12 refrigerant charge= 26-28 Oz plus 6-8 Oz R12 mineral oil on an empty system. A recharge may only require 2-4 OZ of R12 mineral oil if you only replaced a line, hose or seals.
A/C systems that have had a compressor failure must be flushed. Failure to do so will result in the floating trash left behind from the compressor failure destroying the replacement compressor.
R134a = $11-$16 a can – takes 2 cans.
R134a PAG or Ester compatible oil = $7-$12 for an 8 oz bottle .
Pump to force cleaning fluid through the system $20-$50 (may use compressed air to do the same thing).
R134a charging adapter = $13 (I cut mine up to use it with the R12 gauge set that I have had for a long time).
Plastic tools to disconnect refrigerant lines - 1/2" & 5/8" = $4 each.
Flushing agent - Discount Auto Parts has some flushing solvent in a 1 gallon plastic bottle - try that first. Or use Mineral spirits = $4-$5 a gallon, tetrachloroethylene =$5-$10 a gallon, takes 2 gallons of either one.
Miscellaneous hoses and fittings to adapt the flushing pump to the system, and the R134a adapter to the R12 gauge set = $15.
R134 Refrigerant charge is 26-28 Oz plus 6-8 Oz of PAG 100 oil.
R134 Conversion Instructions:
I did a R134a conversion on my 89GT, and used all stock parts. You will need to replace the dryer/receiver (about $75 if you get the one with the hose made as part of the unit), and should replace all of the rubber "O" ring seals as well. You will need to drain all of the oil out of the compressor and replace it with new R134a compatible oil.
R134 instructions (skip this if you use Freeze 12)
Keep in mind that to fulfill the requirements of the EPA, you are required by law to recover any refrigerant that still remains in the system. How (or wither or not) you accomplish this is up to you. Connect the charging gauge hoses to the service ports on the A/C (red gauge = high pressure, blue gauge = low pressure) and open the valves on the gauges to dump the remaining refrigerant (if any) into your "Freon recovery system", whatever it may be. Disconnect the charging gauges since you are finished with them until you are ready to fill the system with R134a. Next comes the nasty part – in order to get all the old oil out of the system, you will need to flush it with special flushing solvent, or mineral spirits (ok) or tetrachloroethylene (better, but may be hard to get). If you leave the old oil in place it will congeal and reduce the heat transfer in the condenser and evaporator (read that it won’t cool good) and possibly damage the compressor.
Disconnect the compressor and remove it from its mount to flush it with cleaning solvent. Pour about a cup of solvent into the suction port and turn the compressor center hub about 10 turns while shaking the compressor to move the solvent around inside the compressor sump. Drain the flushing solvent out and continue to turn the center hub by hand to force out any remaining solvent. Then fill it with oil: add about 6-8 oz of the new oil to the compressor large suction fitting. Turn the compressor center hub about 20 turns as you turn the compressor face up and face down to distribute the new oil inside the compressor. Catch and replace any oil that comes out of the compressor.
Connect the pump (I had an electric sump pump I bought for $20) to the hose from the high-pressure side of the compressor. Alternately, you could use compressed air to force the cleaning fluid through the system. I didn’t like to do this since compressed air has lots of moisture in it, which is death to A/C systems. Pump the cleaning fluid through the system and let it come out the hose that was attached to the old dryer/receiver. I used 2 gallons of mineral spirits and pumped it all through the condenser and evaporator. The expansion valve is located near the firewall in the high-pressure line of the evaporator, and may cause the cleaning fluid to trickle through the lines at a very slow pace. You may want to pump cleaning fluid through the evaporator and condenser separately to speed up the process.
All refrigerant types
Next comes the changing of all the old "O" rings so that the chances for leaks is minimized. The new R134 compatible O rings are green colored, so be sure that the replacement O rings are green. Use the plastic connector tools to separate the lines, place the extended collar part of the tool so that it faces the large part of the connector and push inwards: this expands the spring so that you can pull the tube apart. You may need a helper to push on the tool while you pull on the tubes to separate them. Install the new "O" rings: be sure to coat them with new oil when you put them in. Install the new dryer/receiver, refrigerant service port adapter on the compressor, add about more 4oz of oil to high pressure line and tighten up all the lines. You may have to add more oil when you do a system that has been flushed or new R12 installation. The total oil charge should be 6-8 oz. for all types of refrigerants. Close the hood, start the engine, let everything get warm under the hood, but don’t add the refrigerant or turn the A/C on. Connect the charging gauge hoses to the service ports on the A/C (red gauge = high pressure, blue gauge = low pressure) and open both valves, then connect the center hose to the vacuum pump. The purpose of this exercise is to heat up the system so that when you vacuum it all down (yes, you will need a vacuum pump- mine is an old refrigerator compressor), that all the air, vapor and moisture from the cleaning fluid vaporizes and is removed from the system. Vacuum it down for about 30 minutes, this should give you about 28" of vacuum or more inside the A/C system. I have a vacuum gauge "T" connected into the vacuum pump line so that I can accurately watch the vacuuming process. This is a good time to take a soda and sandwich break since it doesn’t go faster if you watch it.
the R134a service fittings on the system: the red goes on the high side and the blue on the low side. This will help others identify that a R134a conversion has been done on the system.
Typical low pressure side R134 coupling
Typical high pressure side R134 coupling
Charging instructions for all refrigerant types:
Remove the electrical connector from the dryer/receiver and jumper the two connections inside the wiring harness side of the connector together: this allows the compressor to engage in spite of low pressure/no gas in the system. Close both charging gauge valves, and then disconnect the center hose of the charging gauges from the vacuum pump and connect it to the refrigerant can tapper. Put the refrigerant can in the can tapper and screw it down with the can tapper valve closed, then open the valve. Loosen the hose at the center connection of the charging gauge set until the refrigerant squirts out: this purges the line of air and moisture. The refrigerant is added through the low pressure side of the system, so open the low pressure gauge valve to add the refrigerant. Start the car and take note of the idle speed, then set the idle speed up to about 1200-1500 rpm, and turn the A/C on inside and set the fan speed on high. Watch for the pressure on the low side to drop off as you are filling, and the refrigerant can will get warm and stay warm. This tells you the current can is empty and needs to be changed for a fresh one. Before you disconnect the can, be sure to close the valve on the refrigerant can tapper.
Watch the high side pressure on the charging gages and regulate the adding of gas to keep the high side pressure under 350 psi. You will probably need a fan in front of the car to keep the readings below 350 psi. I had to put the refrigerant can in hot water while I was charging the system with it, or else the can got so cold that it quit flowing. Use caution when you do this so that you don’t get water in the charging adapter when you change the cans.
R12 Pressures when charging is complete
When you have added the 32-36 oz. of gas, the high side will read about 250-300 psi and low side about 28-38 psi. No adjustments need to be made to the low pressure cutout switch.
Freeze 12& R134 Pressures when charging is complete.
When you have added the 24-28 oz. of gas, the high side will read about 250-300 psi and low side about 18-28 psi.
Freeze 12 & R134 Low pressure cutout switch adjustment.
The low pressure cutout switches are adjustable. They should be set with the low limit about 18-21 PSI, the stock setting is about 25 PSI. Remove the wiring connector and there is a screw slot in between the connector pins. Turning it clockwise increases the trip pressure where it cuts off and counterclockwise decreases the trip pressure. I believe that each 1/4 turn counterclockwise lowers the cutoff pressure by 1 PSI.
After Charging refrigerant instructions, all refrigerant types
Turn the idle speed back to where it was, turn the A/C off, disconnect the charging gauges, and re-install all the caps on the service ports. Remove the jumper from the low pressure switch harness and plug it back on the switch connectors.
R134 only
Then put the R134a Service Sticker on, secure all the loose wiring on the system and you are done.
The typical sticker looks like this, yours may be different.
I hope it cools good, mine doesn’t get quite as cold as it used to driving around town.
Thanks go to WWW.ACKITS.COM for some of the graphics.
Check out their website for parts and the Auto AC Forum.
The above technical note is for informational purposes only, and the end user is responsible for any damages or injury. The end user bears all responsibility for proper recovery/disposal of any R12 refrigerant.
I have EPA 608 and EPA 609 MVAC certification. And yes, you can shortcut the process, but there are negative factors if you do. Sooner or later, something will cease to function like it should. Shoddy work is a time bomb ticking away, waiting to explode.
Even reporting it to the epa is a joke. The ac company next door to us were busting open ac refrigerant INSIDE the shop, it was soo bad at first we thought there was a fire! We had it on video and pics of the oil all over several vehicles parked in our lot including MY truck. And yes I went balistic! One guy in our shop got a headache so bad he had to go home.
EPA did nothing! Would not even update me on the case and I was the one reporting it. I even but a written public records request, that was months ago and still nothing.
Alright so I pulled the connector
Jumped and closed the circuit saw sparks ac
clutch didnt click
Hoping it was the right connector
Also found a black wire that was tied in above that connector all the way to connector that goes to the ac connector seems to be a ground idk why it's there
Jumped and closed the circuit saw sparks ac
clutch didnt click
Hoping it was the right connector
Also found a black wire that was tied in above that connector all the way to connector that goes to the ac connector seems to be a ground idk why it's there
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You need to jump it and check the connector at the compressor with a test light. If you have power at the connector then you need the clutch assembly. This part is usually cheaper at the local parts store.
When I jumped the connector I saw little sparks normal for jumping power to ground and nothing happened with the clutchYou need to jump it and check the connector at the compressor with a test light. If you have power at the connector then you need the clutch assembly. This part is usually cheaper at the local parts store.
- Mar 2, 2015
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Unplug the compressor and jump the switch. If no sparky then the clutch is bad. No spark when tapping wires means the circuit isn't complete. If it sparks it means it's making it all the way to ground...or a short. If you unplug the compressor and it sparks it means there is an issue in the wiring somewhere. There is a diode in the wires about 8 to 10 inches from the compressor ( may be little further or closer ). There are two wires...one is black w/ yellow stripe....one is black w/ green stripe. Im not diffe which side has the diode...but I think it's the yellow one. I've had compressors not work because that part was burned out interrupting the current flow.
So I unplugged the connector from the compressor and there was no spark so I guess it's time for a new clutch
Finally bought a dmm after all my tools were stolen couple days ago. So I had KOEO max a/c on I have a good ground on the black wire but the other black and yellow wire also shows its grounded these are from the plug to the compressor
Use this to make sure your ac wiring is forrect.
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Yup. Sorry for the late responses. There shouldn't be any oil at the front of the compressor. If there is wetness behind the clutch the seal is probably leaking and the whole compressor could need changing.
The clutch area should be dry. Sometimes oil can get slung up there from other leaks like the PS pump.....but it should be dry. You can remove the front bolt and then the C clips and pull the assembly off.
If the connector is unplugged you should get 12v at the connector. If you plug it in and it shows ground and the clutch does not pull in then the clutch winding is bad and shorted.
The clutch area should be dry. Sometimes oil can get slung up there from other leaks like the PS pump.....but it should be dry. You can remove the front bolt and then the C clips and pull the assembly off.
If the connector is unplugged you should get 12v at the connector. If you plug it in and it shows ground and the clutch does not pull in then the clutch winding is bad and shorted.
It's all ground on both wires of the connector so guess I gotta start tracing this dude I bought it from had his son do wiring and its ridiculous lol
The A/C clutch is about $100 new or you can buy a compressor from the junkyard with a working clutch for about $50. The puller is about $21 if you have to buy one, AutoZone may rent you one for free.
The clutch hub is usually what fails, the rubber shock damper shears off from the steel hub and plate. The pulley turns, but the hub doesn't when you power up the A/C.
www.rockauto.com Ford MOTORCRAFT Part # YB289A $39.00
The hub comes off without much problem if you have the puller. You don’t have to do anything with the refrigerant (R12 or R134a), you can replace the clutch without draining and refilling the system. The snap ring hiding inside the hub is the only tricky part.
Remove the nut; remove the snap ring (if present) and then remove the washer. Loosen the puller tool center bolt so that you can get the larger threaded section of the puller screwed into the clutch hub. Tighten up the center bolt on the puller and the clutch hub will come off.
Clutch hub puller tool
Part Number: 27002
Alternate Part Number: 59509
AutoZone and most other major auto parts chain stores will rent or loan the puller. Cost is $21.00 if they don’t have one to loan.
A few simple electrical tests are advised before popping out the wallet to buy a clutch assembly. With the engine running, use a test light connected to the 2 wires on the A/C clutch harness to make sure you have voltage when you turn the A/C on. If the system is low on refrigerant, the clutch will not engage (safety feature, keeps you from burning up the compressor due to no oil). There is an aluminum canister on the firewall with a large hose leading to the A/C compressor. There is a pressure switch on it with a 2 wire connector: pull the connector off and jumper the wires. The compressor circuit will power up, and the test light will light if the electrical circuit is good. This test is also a good way to check the compressor & clutch if the system is low on refrigerant. You can jumper the wires and the compressor will turn if the clutch is good.
The clutch also has a relay that shuts off when you go to WOT (wide open throttle). It is located on the passenger side inner fender well. The close proximity of the relay to the headers can cause the insulation on the wiring and the relay socket to deteriorate. The relay can become non functional when this happens.
Caution: replacing the A/C compressor seal requires removing the R12 refrigerant. By law you are supposed to recover it and not dump it to open air. I will leave that up to you...
The A/C compressor seal is less than $12. See AutoZone Santech A/C Compressor Shaft Seal Kit MT2039. You will need a pair of internal snap ring pliers to remove and install the seal snap ring
Diagram courtesy of Tmoss & Stang&2birds
See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host) for help on 88-95 wiring http://www.veryuseful.com/mustang/tech/engine/ Everyone should bookmark this site.
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