AC Question
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From: Bergen County, NJ Democrats, doing for the country what they did for Michigan
Yes, sounds good....but if you have to:
2. If leaks, fix them and fill it
You will need to draw down the system(ie vacuum down) to remove moisture from the system before you "fill it". Once you open your system to the atmoshere, air and mositure immediatley enter.....When I do R134 work, I duct tape an AC hose to my shop vac and hook it up to the Low side and let it suck for 30 minutes, then do the same on the High side....I have never had any problems with this method...
2. If leaks, fix them and fill it
You will need to draw down the system(ie vacuum down) to remove moisture from the system before you "fill it". Once you open your system to the atmoshere, air and mositure immediatley enter.....When I do R134 work, I duct tape an AC hose to my shop vac and hook it up to the Low side and let it suck for 30 minutes, then do the same on the High side....I have never had any problems with this method...
Such a PIA because of the R12....
Safety Car
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From: :45 minutes from everywhere / E-I-E-I-O
Safety Car
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From: :45 minutes from everywhere / E-I-E-I-O
I'd put the R-12's on ebay, and convert to R134.
Safety Car
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From: :45 minutes from everywhere / E-I-E-I-O
Fick and GA are right on the money and I apologize for missing this. What you need to do is visually look at all your AC connection points for residue from a leak. Check the rubber hoses as well, as they can also develop pin hole leaks over time. I too have an R12 system in my '93, and this stuff costs more per ounce than gold !! (not really, but it will cost alot, assuming you can find a shop that still deals with R12).
You were right the first time.
If his orifice tube is plugged, it don't make no matter nevermind anywho whatever HOW much freon is recharged into the lines.
So I have three cans, 14oz each
Last edited by schrade; May 4, 2008 at 10:45 PM.
Advanced
Joined: Jan 2008
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From: Salt Lake City UT
ac is painful
As an HVAC tech, imo, R-134a sucks. R-12 is awsome. problem R-12 is regetably "liquid gold" as we call it, and is availble, for a nominal fee. If you know someone in the a/c trade, give him 50 bucks to look at it. they will be able to check the system out, check pressures, switches, superheat, subcooling, general operation. If you ask a tech what superheat or subcooling is, and he answers, "uh, uh, I don't know" don't let him touch your car. or take it to a real auto a/c repair shop. it will be painful either way.
Safety Car
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From: :45 minutes from everywhere / E-I-E-I-O
As an HVAC tech, imo, R-134a sucks. R-12 is awsome. problem R-12 is regetably "liquid gold" as we call it, and is availble, for a nominal fee. If you know someone in the a/c trade, give him 50 bucks to look at it. they will be able to check the system out, check pressures, switches, superheat, subcooling, general operation. If you ask a tech what superheat or subcooling is, and he answers, "uh, uh, I don't know" don't let him touch your car. or take it to a real auto a/c repair shop. it will be painful either way.
As a non-BillGates-type, I wouldn't put R-12 (liquid gold) in 20 year old plumbing.
Advanced
Joined: Jan 2008
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From: Salt Lake City UT
as I also agree, for the average car owner. converting will mostlikely be the best option, if a leak / low charge is the problem. it could possibly be a pressure switch that may be defective. or half dozen possible problems, it would be best to have a shop look at it. one you know is not going to rip you off. good luck.
Last edited by sharp90; May 4, 2008 at 11:44 PM.
Advanced
Joined: Jan 2008
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From: Salt Lake City UT
Yes, sounds good....but if you have to:
2. If leaks, fix them and fill it
You will need to draw down the system(ie vacuum down) to remove moisture from the system before you "fill it". Once you open your system to the atmoshere, air and mositure immediatley enter.....When I do R134 work, I duct tape an AC hose to my shop vac and hook it up to the Low side and let it suck for 30 minutes, then do the same on the High side....I have never had any problems with this method... I just refuse to pay these rediculous prices to "AC specialists" for work....It 'aint rocket science as they would have you believe....It's simple closed system refridgeration that has been around for decades!!!
2. If leaks, fix them and fill it
You will need to draw down the system(ie vacuum down) to remove moisture from the system before you "fill it". Once you open your system to the atmoshere, air and mositure immediatley enter.....When I do R134 work, I duct tape an AC hose to my shop vac and hook it up to the Low side and let it suck for 30 minutes, then do the same on the High side....I have never had any problems with this method... I just refuse to pay these rediculous prices to "AC specialists" for work....It 'aint rocket science as they would have you believe....It's simple closed system refridgeration that has been around for decades!!!
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From: Bergen County, NJ Democrats, doing for the country what they did for Michigan
What's involved with that in terms of cost/work?
If I can get the R12 going for this year, that's good enough for me, I can worry about that next year.
Unless I have to replace the compressor, I can't see the conversion being fiscally responsible. The 134A compressor on Rock Auto is $700 vs. $500 for an R12 compressor.
I don't see where a conversion makes sense, plus, I LOVE THE COLDNESS of R12.
If I can get the R12 going for this year, that's good enough for me, I can worry about that next year.
Unless I have to replace the compressor, I can't see the conversion being fiscally responsible. The 134A compressor on Rock Auto is $700 vs. $500 for an R12 compressor.
I don't see where a conversion makes sense, plus, I LOVE THE COLDNESS of R12.
Le Mans Master
Joined: May 2006
Posts: 9,226
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From: Irvine Ca
yeah, I was going to take issue with that idea as well.
Shop vac=High CFM low base pressure....very very low base pressure
Vacuum pump for A/Cs=very low Cfm and decent base pressure of rough vacuum....10e -2 ish area
jsup, if your system is just low.....2-3 cans is way over kill. Understand it is like filling your tire when you see it down to 25psi....you only need to shoot a bit of air in there to bring it back to 35psi.......same thing for your a/c, you'll need half a can to bring the high side pressure up to spec. You only need 2-3 cans to fill the thing from the starting point of empty....
Shop vac=High CFM low base pressure....very very low base pressure
Vacuum pump for A/Cs=very low Cfm and decent base pressure of rough vacuum....10e -2 ish area
jsup, if your system is just low.....2-3 cans is way over kill. Understand it is like filling your tire when you see it down to 25psi....you only need to shoot a bit of air in there to bring it back to 35psi.......same thing for your a/c, you'll need half a can to bring the high side pressure up to spec. You only need 2-3 cans to fill the thing from the starting point of empty....
Last edited by jhammons01; May 5, 2008 at 12:50 PM.
Pro
Joined: Oct 2003
Posts: 506
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From: Savannah GA
I'm with the last poster. You're about 1/2 can low. Just take you're can rig, connect it to the accumulator port and feed in R12 until the compressor stops cycling when you hold the engine to 2000rpm. DONE until next summer!
If your compressor doesn't rattle bad oil is OK.
Oil leak on early C4 is mostly out the compressor front seal. See an oil streak on the bottom of the hood?
Keep R12 in it as long as you can. Then go to one of the mixes that don't require an oil change. I'm with others, R134 is not #1 way to go for a vette.
JS
If your compressor doesn't rattle bad oil is OK.
Oil leak on early C4 is mostly out the compressor front seal. See an oil streak on the bottom of the hood?
Keep R12 in it as long as you can. Then go to one of the mixes that don't require an oil change. I'm with others, R134 is not #1 way to go for a vette.
JS
Melting Slicks
Joined: Oct 2004
Posts: 2,510
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From: Austin Texas
yeah, I was going to take issue with that idea as well.
Shop vac=High CFM low base pressure....very very low base pressure
Vacuum pump for A/Cs=very low Cfm and decent base pressure of rough vacuum....10e -2 ish area
jsup, if your system is just low.....2-3 cans is way over kill. Understand it is like filling your tire when you see it down to 25psi....you only need to shoot a bit of air in there to bring it back to 35psi.......same thing for your a/c, you'll need half a can to bring the high side pressure up to spec. You only need 2-3 cans to fill the thing from the starting point of empty....
Shop vac=High CFM low base pressure....very very low base pressure
Vacuum pump for A/Cs=very low Cfm and decent base pressure of rough vacuum....10e -2 ish area
jsup, if your system is just low.....2-3 cans is way over kill. Understand it is like filling your tire when you see it down to 25psi....you only need to shoot a bit of air in there to bring it back to 35psi.......same thing for your a/c, you'll need half a can to bring the high side pressure up to spec. You only need 2-3 cans to fill the thing from the starting point of empty....
Thread Starter
Team Owner
Joined: Oct 2004
Posts: 35,065
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From: Bergen County, NJ Democrats, doing for the country what they did for Michigan
yeah, I was going to take issue with that idea as well.
Shop vac=High CFM low base pressure....very very low base pressure
Vacuum pump for A/Cs=very low Cfm and decent base pressure of rough vacuum....10e -2 ish area
jsup, if your system is just low.....2-3 cans is way over kill. Understand it is like filling your tire when you see it down to 25psi....you only need to shoot a bit of air in there to bring it back to 35psi.......same thing for your a/c, you'll need half a can to bring the high side pressure up to spec. You only need 2-3 cans to fill the thing from the starting point of empty....
Shop vac=High CFM low base pressure....very very low base pressure
Vacuum pump for A/Cs=very low Cfm and decent base pressure of rough vacuum....10e -2 ish area
jsup, if your system is just low.....2-3 cans is way over kill. Understand it is like filling your tire when you see it down to 25psi....you only need to shoot a bit of air in there to bring it back to 35psi.......same thing for your a/c, you'll need half a can to bring the high side pressure up to spec. You only need 2-3 cans to fill the thing from the starting point of empty....
Safety Car
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......depends on capacity of system and how much currently remains in same...there shoud be a data plate/sticher either on the compressor or on the body of the heater core cover that should state the capacity...a set of gauges is the ONLY SURE WAY of getting an accurate reading....
Safety Car
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Just checked. I have FOUR 14oz cans. However, one is empty, guess over time it leaked out. So I have three cans, 14oz each.
That should be enough, no?
I also have the hose adapter for the can.
Problem. It's FORD MOTOCRAFT R12. Kinda like Jerry Sienfeld getting a blood transfusion from Newman, eh?
That should be enough, no?
I also have the hose adapter for the can.
Problem. It's FORD MOTOCRAFT R12. Kinda like Jerry Sienfeld getting a blood transfusion from Newman, eh?
Safety Car
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.....needs to be added separately....getting a bit hard to find though.....
Safety Car
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No, there is no oil in the R12 cans you have, unless it explicitly says so on the can.....It will probably be difficult to find R12 oil charge nowadays. Chances are, since your AC system is still cycling , you still have plenty of oil in the system....
Remember....make sure you first try to locate the leak. If you find that you have a bad hose, BLAM, it will have to be replaced, system will have to be evacuated, and re-charged. If this is the case, good to replace the oriface tube(chap) and the reciever dryer....
On the other hand, if you can't find a major source of leak, I would just give a quick "torque" to all the connections, hook up the gauges and charge to specified High/Low pressure....(I don't know these numbers off hand....)
A good rule of thumb is ~30psi on the Low side and ~200psi on the High.......
Remember....make sure you first try to locate the leak. If you find that you have a bad hose, BLAM, it will have to be replaced, system will have to be evacuated, and re-charged. If this is the case, good to replace the oriface tube(chap) and the reciever dryer....
On the other hand, if you can't find a major source of leak, I would just give a quick "torque" to all the connections, hook up the gauges and charge to specified High/Low pressure....(I don't know these numbers off hand....)
A good rule of thumb is ~30psi on the Low side and ~200psi on the High.......
on finding the leak...if not visible, could be in teh evaporator housing....you could use a leak detector for that one by placing prob of same in vent...
Safety Car
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Yes, sounds good....but if you have to:
2. If leaks, fix them and fill it
You will need to draw down the system(ie vacuum down) to remove moisture from the system before you "fill it". Once you open your system to the atmoshere, air and mositure immediatley enter.....When I do R134 work, I duct tape an AC hose to my shop vac and hook it up to the Low side and let it suck for 30 minutes, then do the same on the High side....I have never had any problems with this method... I just refuse to pay these rediculous prices to "AC specialists" for work....It 'aint rocket science as they would have you believe....It's simple closed system refridgeration that has been around for decades!!!
2. If leaks, fix them and fill it
You will need to draw down the system(ie vacuum down) to remove moisture from the system before you "fill it". Once you open your system to the atmoshere, air and mositure immediatley enter.....When I do R134 work, I duct tape an AC hose to my shop vac and hook it up to the Low side and let it suck for 30 minutes, then do the same on the High side....I have never had any problems with this method... I just refuse to pay these rediculous prices to "AC specialists" for work....It 'aint rocket science as they would have you believe....It's simple closed system refridgeration that has been around for decades!!!
Last edited by Da Mail Man; May 5, 2008 at 09:33 PM. Reason: additional and spelling errors
Safety Car
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