Need AC help
Thread Starter
Le Mans Master
Joined: Jan 2004
Posts: 8,295
Likes: 30
From: one night in Bangkok you are never lonely
Need AC help
I have in the past year installed three original type rebuilt compressors and now have a Sanden that works OK. I have replaced everything else but the Condenser plus I have four fans one on the engine plus the original electric fan behind the radiator plus two more in front attached to the condenser. But with all the extra fans I still have the same old problem of when I get in just a little stop and go traffic or even a little long light the compressor starts to drag the RPMs down and I can feel it straining. But when moving it is fine blowing cold. I believe the Freon is not condensing causing liquid and not gas threw the system causing the compressor to bind up.
The engine temperature never get hot but the darn AC is driving me crazy.
I have posted before on this but get all kinds of advise on cooling the engine but that is never a problem
The engine temperature never get hot but the darn AC is driving me crazy.
I have posted before on this but get all kinds of advise on cooling the engine but that is never a problem
Safety Car
Joined: Mar 2005
Posts: 3,503
Likes: 2
From: Raleigh NC
It's condensing--if the temperature reached the point where it wouldn't, you would have already seen a total catastrophic failure of--something in the system. At least the high pressure blowout plug would have released.
You definitely could be overcharged. This would increase the high pressure side to the point where too much refrigerant is entering the evaporator coil--flooding the evaporator--and returning liquid refrigerant back to the compressor. Which compressors do not like at all--which may explain your parade of replacement compressors.
What type of refrigerant are you using?
How much did you charge?
What type of flexible refrigerant lines are you using (stock or replacement?)
Any under drive pulley's?
What type of orifice tube? The variable ones now available are just **** for stop & go traffic.
You definitely could be overcharged. This would increase the high pressure side to the point where too much refrigerant is entering the evaporator coil--flooding the evaporator--and returning liquid refrigerant back to the compressor. Which compressors do not like at all--which may explain your parade of replacement compressors.
What type of refrigerant are you using?
How much did you charge?
What type of flexible refrigerant lines are you using (stock or replacement?)
Any under drive pulley's?
What type of orifice tube? The variable ones now available are just **** for stop & go traffic.
Melting Slicks
Joined: May 2002
Posts: 2,716
Likes: 121
From: Sulphur LA
St. Jude Donor '05-'06,'11,'13-'14,'16,'18,'19,'24, '25
Dean does your car have an idle solenoid? If so you may look at it, if not do you have a set of service gauges to see what’s going on with the system when it starts acting up? The possibility of liquid getting back to the comp is not likely, it would only take a very little liquid to destroy the comp, one cause of liquid getting to the comp would be a very cold day and the system being way over charged. I am assuming that you think it's the A/C because when it starts acting up you can turn the A/C off and it idles fine. How are the extra fans wired? If they are wired to run with the A/C maybe the extra load on the electrical system along with the A/C could be taxing the engine at idle, you may have the electrical system (alt)checked out.
Neal
Neal
Thread Starter
Le Mans Master
Joined: Jan 2004
Posts: 8,295
Likes: 30
From: one night in Bangkok you are never lonely
PhotoVette1]
What type of refrigerant are you using?R12
How much did you charge?Not sure had AC shop charge system over here we use AC year round so there are many shops.What type of flexible refrigerant lines are you using (stock or replacement?)Some stock some braided Stainless steel.
Any under drive pulley's?Stock pulleys on engine and on the sanden the one that comes with it.
What type of orifice tube? The variable ones now available are just **** for stop & go traffic. Sorry dont know what this part is???
[quote]Dean does your car have an idle solenoid? If so you may look at it, if not do you have a set of service gauges to see what’s going on with the system when it starts acting up? The possibility of liquid getting back to the comp is not likely, it would only take a very little liquid to destroy the comp, one cause of liquid getting to the comp would be a very cold day and the system being way over charged. I am assuming that you think it's the A/C because when it starts acting up you can turn the A/C off and it idles fine. How are the extra fans wired? If they are wired to run with the A/C maybe the extra load on the electrical system along with the A/C could be taxing the engine at idle, you may have the electrical system (alt)checked out.
Neal[quote]
I had this problem long before I added the extra fans. No I don't have an idle solenoid but I run a high idle with AC off 900 RPM, when it acts up and I turn off the AC it idles fine and the binding feeling stops.
What type of refrigerant are you using?R12
How much did you charge?Not sure had AC shop charge system over here we use AC year round so there are many shops.What type of flexible refrigerant lines are you using (stock or replacement?)Some stock some braided Stainless steel.
Any under drive pulley's?Stock pulleys on engine and on the sanden the one that comes with it.
What type of orifice tube? The variable ones now available are just **** for stop & go traffic. Sorry dont know what this part is???
[quote]Dean does your car have an idle solenoid? If so you may look at it, if not do you have a set of service gauges to see what’s going on with the system when it starts acting up? The possibility of liquid getting back to the comp is not likely, it would only take a very little liquid to destroy the comp, one cause of liquid getting to the comp would be a very cold day and the system being way over charged. I am assuming that you think it's the A/C because when it starts acting up you can turn the A/C off and it idles fine. How are the extra fans wired? If they are wired to run with the A/C maybe the extra load on the electrical system along with the A/C could be taxing the engine at idle, you may have the electrical system (alt)checked out.
Neal[quote]
I had this problem long before I added the extra fans. No I don't have an idle solenoid but I run a high idle with AC off 900 RPM, when it acts up and I turn off the AC it idles fine and the binding feeling stops.
Melting Slicks
Joined: May 2002
Posts: 2,716
Likes: 121
From: Sulphur LA
St. Jude Donor '05-'06,'11,'13-'14,'16,'18,'19,'24, '25
Dean may need to run it by the shop when it is acting up so you can get an idea of what is going on inside the system. The old A/C comp could use as much as 10 HP to operate although this is alot I don't think it would cause the problem your describing short of seizing up. With the new sanden comp it uses even less, we really need to know what the operating pressures are in the system when it starts acting up. You say you changed 2 old style comp's before you went with the sanden, what happened to the other comp's? We don't have very good luck with the rebuilts over here, they will usually fail within a year. you will get a good one every once in a while.
Neal
Neal
Race Director
Joined: Mar 2006
Posts: 14,112
Likes: 27
From: Florida
Originally Posted by chevymans 77
Dean may need to run it by the shop when it is acting up so you can get an idea of what is going on inside the system. The old A/C comp could use as much as 10 HP to operate although this is alot I don't think it would cause the problem your describing short of seizing up. With the new sanden comp it uses even less, we really need to know what the operating pressures are in the system when it starts acting up. You say you changed 2 old style comp's before you went with the sanden, what happened to the other comp's? We don't have very good luck with the rebuilts over here, they will usually fail within a year. you will get a good one every once in a while.
Neal
Neal
You can't even make educated guesses without knowing the pressures and most of the answers below.
At approx 1500 rpm, with a/c function switch set at normal, temp control to "cold" (not recirculating cockpit air):
-measure ambient air temp approx 2" in front of condenser
-measure center dash vent air temp with blower on high
-measure temp at top of dash
-high side pressure
-low side pressure
Did they remove and flush evaporator after each compressor failure?
Was the rest of the system flushed?
Was the orifice tube replaced?
What no. oriface or color is in it?
Was the drier/accum replaced?
What model Sanden did they put in?
What type and viscosity of oil was put in?
What amount of oil was put in?
Can you post a pic of the condenser mounted on the rad support?
Thread Starter
Le Mans Master
Joined: Jan 2004
Posts: 8,295
Likes: 30
From: one night in Bangkok you are never lonely
Originally Posted by chevymans 77
Dean may need to run it by the shop when it is acting up so you can get an idea of what is going on inside the system. The old A/C comp could use as much as 10 HP to operate although this is alot I don't think it would cause the problem your describing short of seizing up. With the new sanden comp it uses even less, we really need to know what the operating pressures are in the system when it starts acting up. You say you changed 2 old style comp's before you went with the sanden, what happened to the other comp's? We don't have very good luck with the rebuilts over here, they will usually fail within a year. you will get a good one every once in a while.
Neal
Neal
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Thread Starter
Le Mans Master
Joined: Jan 2004
Posts: 8,295
Likes: 30
From: one night in Bangkok you are never lonely
[QUOTE=noonie]
Did they remove and flush evaporator after each compressor failure?No they evacuated onlyWas the rest of the system flushed?No they evacuated only
Was the orifice tube replaced?Still don't know what that is?????
What no. oriface or color is in it?Still don't know what that is?????
Was the drier/accum replaced?Everything was replaced to new parts
What model Sanden did they put in?508
What type and viscosity of oil was put in?Don't know
What amount of oil was put in?Also don't know
Can you post a pic of the condenser mounted on the rad support This is difficult must remove hood to take the picture. But it is the original radiator brackets and condenser
As I mentioned above I will try to get some readings in the next couple of days. Also the AC runs cold and engine runs good when the car is moving. The problems happens when idling in stop conditions.
Did they remove and flush evaporator after each compressor failure?No they evacuated onlyWas the rest of the system flushed?No they evacuated only
Was the orifice tube replaced?Still don't know what that is?????
What no. oriface or color is in it?Still don't know what that is?????
Was the drier/accum replaced?Everything was replaced to new parts
What model Sanden did they put in?508
What type and viscosity of oil was put in?Don't know
What amount of oil was put in?Also don't know
Can you post a pic of the condenser mounted on the rad support This is difficult must remove hood to take the picture. But it is the original radiator brackets and condenser
As I mentioned above I will try to get some readings in the next couple of days. Also the AC runs cold and engine runs good when the car is moving. The problems happens when idling in stop conditions.
Last edited by Bangkok Dean; Jul 23, 2006 at 02:08 PM.
Race Director
Joined: Mar 2006
Posts: 14,112
Likes: 27
From: Florida
Dean,
Just for the fun of it try to get some pics without removing the hood. Maybe you can just hold the camera and guess at aiming it.
Need the info, can't guess a diagnosis.
Just print out the questions and have the shop give you the answers if that is possible. Or buy a cheap set of guages. You can get everything else over there dirt cheap; fake watches etc. LOL
Just for the fun of it try to get some pics without removing the hood. Maybe you can just hold the camera and guess at aiming it.
Need the info, can't guess a diagnosis.
Just print out the questions and have the shop give you the answers if that is possible. Or buy a cheap set of guages. You can get everything else over there dirt cheap; fake watches etc. LOL
Burning Brakes
Joined: Nov 2004
Posts: 899
Likes: 1
From: Kansas
Originally Posted by Bangkok Dean
What is the orifice tube?
Instructor
Joined: Nov 2002
Posts: 115
Likes: 0
From: Brandon FL
Le Mans Master
Joined: Jul 2005
Posts: 5,752
Likes: 4
From: Austin Texas
Originally Posted by Bangkok Dean
What is the orifice tube?
Melting Slicks
Joined: May 2002
Posts: 2,716
Likes: 121
From: Sulphur LA
St. Jude Donor '05-'06,'11,'13-'14,'16,'18,'19,'24, '25
Dean
The orifice tub is a calculated metering device that causes the medium temp, high pressure liquid refrigerant to drop to a low pressure gas, this change in phase causes the refrigerant to give up its heat and causes the cooling effect you feel at the evaporator. It’s a small device that is in the inlet line to the evaporator, there are two inset areas in the line right at the line connection on the inlet of the evaporator, and these insets hold the orifice tub in place. Because the orifice is so small there is a screen on the inlet of the orifice so it does not get plugged easily. Just type GM orifice tub into Goggle and you can get a pic of one.
Neal
The orifice tub is a calculated metering device that causes the medium temp, high pressure liquid refrigerant to drop to a low pressure gas, this change in phase causes the refrigerant to give up its heat and causes the cooling effect you feel at the evaporator. It’s a small device that is in the inlet line to the evaporator, there are two inset areas in the line right at the line connection on the inlet of the evaporator, and these insets hold the orifice tub in place. Because the orifice is so small there is a screen on the inlet of the orifice so it does not get plugged easily. Just type GM orifice tub into Goggle and you can get a pic of one.
Neal
Melting Slicks
Joined: Dec 2000
Posts: 3,407
Likes: 2
From: Carmichael CA
Originally Posted by Bangkok Dean
Thanks guys. Today I found my original idle solenoid. So now I will install it. I will check on the Orifice tube this week.
When the shop flushed my system he was amazed to find almost a quart of oil in the condensor...almost 1/2 of the condensor was filled with oil. That's way too much oil, which means that very little freon was in the system. My guess is that the shop barely got 2 or 2-1/2 lbs of freon into your system while it should have accepted like 3 or 3-1/4. Have them flush the system...my shop mechanic said he spent almost a full 30 minutes pouring A/C system flush fluid through the condensor alone.
Thread Starter
Le Mans Master
Joined: Jan 2004
Posts: 8,295
Likes: 30
From: one night in Bangkok you are never lonely
Originally Posted by Rockn-Roll
My thoughts...I don't think Idle solenoid is going to make any difference. What I see is as the problem is that the system was never flushed. I'm thinking that in Bangkok there aren't too many A/C systems with such a large condenser and so they don't flush every unit that comes in unless there is a problem with contamination.
When the shop flushed my system he was amazed to find almost a quart of oil in the condenser...almost 1/2 of the condenser was filled with oil. That's way too much oil, which means that very little freon was in the system. My guess is that the shop barely got 2 or 2-1/2 lbs of freon into your system while it should have accepted like 3 or 3-1/4. Have them flush the system...my shop mechanic said he spent almost a full 30 minutes pouring A/C system flush fluid through the condensor alone.
When the shop flushed my system he was amazed to find almost a quart of oil in the condenser...almost 1/2 of the condenser was filled with oil. That's way too much oil, which means that very little freon was in the system. My guess is that the shop barely got 2 or 2-1/2 lbs of freon into your system while it should have accepted like 3 or 3-1/4. Have them flush the system...my shop mechanic said he spent almost a full 30 minutes pouring A/C system flush fluid through the condensor alone.
I will try to pull the condenser to have it flushed out.
