AC hasn't worked since wreck. Steps to troubleshoot/recharge on the cheap?
05-30-2013, 01:52 PM
#1
AC hasn't worked since wreck. Steps to troubleshoot/recharge on the cheap? So a few years back I wrecked my car. I was at fault and only had liability so I was out of pocket for fixing the car which included fixing the radiator (one of the plastic tanks along the side got cracked.) I put in an old LT1 radiator myself which was a total bitch. Ever since, the AC has failed to work. And I've burned up since.
So of course my first thought is to go buy one of those recharge kits you always see. But where can I get the dye to test for a leak before I were to get a recharge kit? Where do you even put that stuff in at? I have the same question about where you put those recharge kits.
I've done a search and read up on a few threads where people who regularly do AC work call these cans suicide but there is NO way in hell I'm paying 600$ or more to redo my AC- I'll burn up first. Especially after reading about people paying that amount only to still have hot air blowing them in the face.
Another question I have is how can I tell when the compressor is cutting on or off in order to rule that out? What kind of noise am I looking for and what is the best place to listen for it?
So of course my first thought is to go buy one of those recharge kits you always see. But where can I get the dye to test for a leak before I were to get a recharge kit? Where do you even put that stuff in at? I have the same question about where you put those recharge kits.
I've done a search and read up on a few threads where people who regularly do AC work call these cans suicide but there is NO way in hell I'm paying 600$ or more to redo my AC- I'll burn up first. Especially after reading about people paying that amount only to still have hot air blowing them in the face.
Another question I have is how can I tell when the compressor is cutting on or off in order to rule that out? What kind of noise am I looking for and what is the best place to listen for it?
05-30-2013, 02:07 PM
#2
Its not easy to just blow these systems up....BUT if you have no knowledge at all about A/C I wouldnt recommend you adding 134 to it. blowing something up could just be a hose popping off or splitting but if youre standing right there something could blow in a way to hit you with pieces of metal or rubber.
You hook the A/C refill hose to the large port on the big silver can......the evap canister. Its the silver canister near the battery that gets cold and wet when the A/C is on. It won't hook to the little port near the radiator anyway. You use the LARGER of the two ports.
I'm no A/C expert...but many times over the years I've simply bought two cans of 134 w/oil mixed in them and a 2-3 ounce can of extra oil. Put one can of 134 in......then the oil can, then the other 134 till it was ice cold. It never took two full cans when I would do recharges. It was ice cold about halfway through the second can.
That's the cheapest possible way to recharge a system. But get it vacuumed down if the system has been wide open for a long time.
.
You hook the A/C refill hose to the large port on the big silver can......the evap canister. Its the silver canister near the battery that gets cold and wet when the A/C is on. It won't hook to the little port near the radiator anyway. You use the LARGER of the two ports.
I'm no A/C expert...but many times over the years I've simply bought two cans of 134 w/oil mixed in them and a 2-3 ounce can of extra oil. Put one can of 134 in......then the oil can, then the other 134 till it was ice cold. It never took two full cans when I would do recharges. It was ice cold about halfway through the second can.
That's the cheapest possible way to recharge a system. But get it vacuumed down if the system has been wide open for a long time.
.
Last edited by LS6427; 05-30-2013 at 02:16 PM.
05-30-2013, 02:11 PM
#3
Oh. When the A/C is turned to the "on" position......the clutch will engage and it makes a rather noticeable CLICK sound. Or just have a friend get in the car and turn the A/C on and off and you can look down at the front of the compressor and see the wheel start to turn and then stop turning as he turns it on and off.
Also.....when its turned on....the engine idle will drop down slightly for a second or two, then come back to normal idle rpm.
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Also.....when its turned on....the engine idle will drop down slightly for a second or two, then come back to normal idle rpm.
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05-30-2013, 02:51 PM
#4
without really knowing how bad the AC system is, i would suggest you get a $50 gauge set from harbor freight or wherever to check system pressures first. you might be able to have any shop do this for free. my guess is since it was "wrecked" and you needed a new radiator, you also wrecked the AC condenser mounted in front of the radiator.
http://www.harborfreight.com/a-c-man...set-92649.html
there's 2 gauges and 2 hoses. red gauge is high pressure side and can only connect to the high pressure service port. blue gauge & hose can only connect to low pressure service port. the service ports are different sizes so you can't screw up.
here is a pic of their locations
with the engine off connect your gauges, they are quick connect fittings very easy takes 30 seconds. then open the valve on the hose connector and you'll see the gauges read the system pressure. with engine off both gauges will read the same and should be around 70 psi give or take depending on outside air temp and if the engine is hot and has heat soaked the ac system- if so you could read a static pressure over 100 psi. point here is to see if there is considerable refrigerant in the system. if you read something like 20 psi, or 0, then you know the system has been significantly compromised somewhere and adding any r134a is a complete waste of time and money, and you'll then need to pressurize the system and find the leaks and repair. otherwise if the system is basically holding and you know if you put r134a in it'll last more than a week, then you could do that and hopefully get it working.
i would feel all the ac lines in the engine bay and inspect around the compressor for signs of oil leakage. if there was an oil leak you have 2 options since you don't know how much has leaked- guess at how much to add when charging with r134a, or spend the money to open the system and fix it properly (fix leaks, flush, vacuum, add oil, charge with r134a). my guess is the condenser also got wrecked so the system completely depleted and will show zero pressure on the gauge. if that's the case then you will at least need a new accumulator. probably new condenser. check condition of lines, replace if necessary otherwise flush. reuse your current compressor by draining the old oil out of it then reinstall. with system all reinstalled, i suggest you take it to a shop which has a machine that can properly pressure test the system for leaks, then vacuum it to remove air and moisture, then inject the correct amount of oil and charge with the correct amount of r134a by weight. you need a very good vacuum pump that will pull a deep vacuum on the ac system, otherwise there will be air in there which is moisture and most likely cause the system to fail within a year.
http://www.harborfreight.com/a-c-man...set-92649.html
there's 2 gauges and 2 hoses. red gauge is high pressure side and can only connect to the high pressure service port. blue gauge & hose can only connect to low pressure service port. the service ports are different sizes so you can't screw up.
here is a pic of their locations
with the engine off connect your gauges, they are quick connect fittings very easy takes 30 seconds. then open the valve on the hose connector and you'll see the gauges read the system pressure. with engine off both gauges will read the same and should be around 70 psi give or take depending on outside air temp and if the engine is hot and has heat soaked the ac system- if so you could read a static pressure over 100 psi. point here is to see if there is considerable refrigerant in the system. if you read something like 20 psi, or 0, then you know the system has been significantly compromised somewhere and adding any r134a is a complete waste of time and money, and you'll then need to pressurize the system and find the leaks and repair. otherwise if the system is basically holding and you know if you put r134a in it'll last more than a week, then you could do that and hopefully get it working.
i would feel all the ac lines in the engine bay and inspect around the compressor for signs of oil leakage. if there was an oil leak you have 2 options since you don't know how much has leaked- guess at how much to add when charging with r134a, or spend the money to open the system and fix it properly (fix leaks, flush, vacuum, add oil, charge with r134a). my guess is the condenser also got wrecked so the system completely depleted and will show zero pressure on the gauge. if that's the case then you will at least need a new accumulator. probably new condenser. check condition of lines, replace if necessary otherwise flush. reuse your current compressor by draining the old oil out of it then reinstall. with system all reinstalled, i suggest you take it to a shop which has a machine that can properly pressure test the system for leaks, then vacuum it to remove air and moisture, then inject the correct amount of oil and charge with the correct amount of r134a by weight. you need a very good vacuum pump that will pull a deep vacuum on the ac system, otherwise there will be air in there which is moisture and most likely cause the system to fail within a year.
06-02-2013, 02:07 PM
#5
Im guessing since your radiator was damaged, so was your condensor since it sits in front of it. Youll have to either replace it or have the leak fixed if the damage is minor. Ive had several small leaks repaired by a radiator shop for cheap. A new one will run you at least $100.
Start by checking for oil stains on the condensor for obvious signs of leaks.
Start by checking for oil stains on the condensor for obvious signs of leaks.
06-02-2013, 02:31 PM
#6
Your compressor is turning on and then back off because the low pressure switch is sensing low freon. It turns off to keep from messing up the compressor. They have refills with dye in them to detect where the leaks are.. I would top the system off, make sure it works and look for the dye coming out. Be sure to clean all the lines associated with the A/C real good, so you will see the leak easier.
