The car is an 88 GT. Doesn't matter how tight I get the A/C belt, it slips and squeals. I can re-tighten the belt, and it's okay for a few minutes, and then starts squealing again. (The adjustment is not slipping.) The belt has been replaced. The one that came on the car broke. With the engine off, I can turn the compressor fairly easily by hand, just by grabbing the clutch. Long story short, it seems like the compressors is dragging, or having a difficult time turning, under power. It does not try to stall the engine, however.
Full disclosure... I had to remove the HVAC airbox to clean out the ductwork, heater, and evap core. I was planning to let the refrigerant escape slowly, so as to retain all the oil. (Yeah... I know.) But instead, the schrader valve blew out and coated the entire right side of the compartment with A/C oil. Lots of it. It gets better. The car had an R134A low side fitting, but the high side still had the R12 fitting, with no R134A adapter. So... what refrigerant was in it was in question. If it had been converted, what oil was even in it? I decided to replace my "lost" oil with Ester oil, since that's supposed to be compatible with PAG and mineral oil. I figured that I had likely vented most of what was in the receiver dryer, since that's where the schrader came from. So I added ~2 oz. (This might be where I messed up.)
I vacuumed the system down, and it held just fine, so I entered the required amount of R134A; ~36 oz., and called it a day. I should add that the A/C will run you out of the car. It cools better than the A/C in any of my other cars.
So... why does my compressor "drag"? Have I possibly got too much oil in the system? I haven't looked at high side pressure yet, but low side seems to be fine. As I said, it seems to work fine, and cycles fine, other than the dragging.
Thanks!
[This message has been edited by Raydar (edited 09-02-2023).]
Raydar, did the belt squeal before the Airbox work and recharge?
About the R134A fitting on the low side and not on the high, I ran into this issue where the high side adapter would not seal so we left that off and charged it Via the Low side port.
This bot has shown up on multiple threads, it looks like its trying to inject malicious code:
<span id="SHOWHIDDEN84984" class="HTMLBodyLink" style="cursor ointer;" onclick="document.getElementById('HIDDEN84984').style.display='';document.getElementById('SHOWHIDDEN84984').style.display='none'"><!-- HIDE_CAPTIONSTART -->Click to see AI response<!-- HIDE_CAPTIONEND --></span>
This bot has shown up on multiple threads, it looks like its trying to inject malicious code: ... Cliff needs to delete its posts.
I checked the announcements. This is a "Cliff" thing. It's supposed to answer questions, but all I've seen so far is it quoting verbatim, with slightly different spacing of phrases.
Raydar, did the belt squeal before the Airbox work and recharge?
About the R134A fitting on the low side and not on the high, I ran into this issue where the high side adapter would not seal so we left that off and charged it Via the Low side port.
I'm not sure. Soon after buying the car, I realized that it had a white mold problem, due to a minor leak in the sunroof. The first order of the day was to gut the interior, Including all the ductwork, and decontaminate everything. I didn't want to take any chances on it coming back.
Good info on the fittings. But even if the car had been converted to R134, I still probably needed to use Ester oil, I'm thinking. I couldn't assume that everything had been disassembled and flushed.
Check the air gap on the clutch coil, and make sure the two metal surfaces are clean, the air gap should be ~0.020".
Considering you had mystery oil (in terms of quantity and type) in before and added Ester oil, there is likely too much oil in the system. Most of it is probably going to settle in the compressor, accumulator, and under-car lines. If you can remove and drain those, then add 8oz of PAG or Ester, that would be ideal to make sure it's closer to spec.
Check the air gap on the clutch coil, and make sure the two metal surfaces are clean, the air gap should be ~0.020". ... there is likely too much oil in the system. Most of it is probably going to settle in the compressor, accumulator, and under-car lines. If you can remove and drain those, then add 8oz of PAG or Ester, that would be ideal to make sure it's closer to spec.
Doesn't some "live" in the condensor and evaporator, too? If I thought I could successfully drain it all without disassembling everything, I'd do it in a hot minute. I didn't think it was that easy. I've got an air compressor. Maybe I could blow everything out. I was thinking that, since I added ~2 oz., maybe I could just remove *almost* 2 oz.
Thanks!
[This message has been edited by Raydar (edited 09-02-2023).]
Doesn't some "live" in the condensor and evaporator, too?
Yes, but not as much as the others. You could drain and flush the whole thing to be sure, but some small amount of residual oil is fine.
quote
I was thinking that, since I added ~2 oz., maybe I could just remove *almost* 2 oz.
Thanks!
This assumes the system had the proper amount to begin with (and wasn't R-12 525 viscosity mineral oil). The fact you pressed the schrader valve and it sprayed 2oz of oil everywhere would seem to suggest there's a LOT of oil in there.
This assumes the system had the proper amount to begin with (and wasn't R-12 525 viscosity mineral oil). The fact you pressed the schrader valve and it sprayed 2oz of oil everywhere would seem to suggest there's a LOT of oil in there.
Shouldn't a good long vacuum evacuate the majority of the oil? say 20 mins under 30 or more inches of vacuum . I do respect your knowledge, just asking an honest inquiry.
If you "put too much oil" and hydrolock the compressor would lock it not cause "Tight" compressor.
Likely the compressor is bad. Or maybe you pulled the belt too tight cause cord layer failure. Many people think the belt need pulled like string for banjo etc. and quickly fail.
------------------ Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should. (Jurassic Park)
This bot has shown up on multiple threads, it looks like its trying to inject malicious code:
<span id="SHOWHIDDEN84984" class="HTMLBodyLink" style="cursor ointer;" onclick="document.getElementById('HIDDEN84984').style.display='';document.getElementById('SHOWHIDDEN84984').style.display='none'"><!-- HIDE_CAPTIONSTART -->Click to see AI response<!-- HIDE_CAPTIONEND --></span>
Cliff needs to delete its posts.
No, it's not injecting malicious quotes. It just puts its response inside a [ hide ][ /hide ] tag. The reason you don't see a URL if you hover over it is because it's not a link.
Looks like ChatGPT showed up to the thread to help you
That's my mistake. It was working properly but I made a small change and made an small error causing the software to display the question instead of the answer.
Shouldn't a good long vacuum evacuate the majority of the oil? say 20 mins under 30 or more inches of vacuum . I do respect your knowledge, just asking an honest inquiry.
It actually doesn't, that's why you can add the oil to the accumulator and compressor before sealing the system up and drawing vacuum.
Originally posted by RWDPLZ: This assumes the system had the proper amount to begin with (and wasn't R-12 525 viscosity mineral oil). The fact you pressed the schrader valve and it sprayed 2oz of oil everywhere would seem to suggest there's a LOT of oil in there.
I didn't just press the schrader. I figured I could unscrew it a few threads and create a slow leak. Wrong-O! Instead, it blew the core into the next county, and a green blast came out of the receiver-drier, where the valve core had previously lived. So there was a nice coating of oil and dye all over the right side of the front compartment, and the underside of the hood, and the jack attachment bracket, and...
And Ogre... I know that I *could* have hydrolocked the compressor, if it was trying to compress just oil. I just figured that maybe there was just enough oil to reduce the volume enough to not hydrolock the compressor, but to make the gas/oil mixture a lot harder to compress. That was actually the gist of my question.
Once again, thanks everyone.
Once I get my blue car ready for RFTH, this is next on the list.
I didn't just press the schrader. I figured I could unscrew it a few threads and create a slow leak. Wrong-O! Instead, it blew the core into the next county, and a green blast came out of the receiver-drier, where the valve core had previously lived. So there was a nice coating of oil and dye all over the right side of the front compartment, and the underside of the hood, and the jack attachment bracket, and...
And Ogre... I know that I *could* have hydrolocked the compressor, if it was trying to compress just oil. I just figured that maybe there was just enough oil to reduce the volume enough to not hydrolock the compressor, but to make the gas/oil mixture a lot harder to compress. That was actually the gist of my question.
Once again, thanks everyone.
Once I get my blue car ready for RFTH, this is next on the list.
What I research online, its called slugging if the compressor has too much oil. Nothing definitive about whether it can cause the belt to squeal. More likely its to do with the pulley or clutch? If you blew out that much oil 2oz isn't really a lot to add back in. If you change the accumulator its 4oz in a new one.
Someone I know, if they want to let the refridge escape slowly, they just loosen 1 of the nuts on the accumulator . They were in a rush on the weekend to get the a/c working and shops weren't open to capture.
[This message has been edited by sdgdf (edited 09-03-2023).]
What I research online, its called slugging if the compressor has too much oil. Nothing definitive about whether it can cause the belt to squeal. More likely its to do with the pulley or clutch? ...
The pulley spins fine, when it's not engaged. The clutch also seems to be doing it's job. I'm pretty sure it's not slipping. It's the belt that's slipping. About the only time I drove the car before the "geyser" was on the way home, and maybe to town a time or two. Then I tore it all down.
Strangely enough, the seller told me that the A/C needed to be charged occasionally. I have never seen that. A year later, it's still so cold it will run you out of the car.
DISCLAIMER: This is an AI generated response. It may produce inaccurate information about people, places, or facts.
Based on your description, it seems like the issue may indeed be with the A/C compressor which is resulting in the persistent belt slippage. The dragging could be a result of a worn-out bearing or clutch in the A/C compressor or alternatively, there might be too much oil in the system.
Even though you mentioned you find it fairly easy to turn the A/C compressor, proper diagnosis requires observation under normal engine operating conditions. The mechanical load imposed by the A/C compressor could be causing excessive slippage when the engine is running, hence the occasional squealing noises.
It's also possible that the oil used could be causing an issue. If your Fiero used to operate on R12, it likely used mineral oil as a lubricant within the system. While Ester oil is indeed compatible with both PAG and mineral oils, it’s main advantage comes into play during refrigerant conversions from R12 to R134a. In an ideal situation, the A/C system should be properly flushed before changing the type of oil to avoid any compatibility issues.
A maxed-out system (overfilled with lubricant) could cause a liquid lock at the compressor as it is not designed to pump liquids, only gas. This might explain your compressor's difficulty or "drag", and the frequent belt slipping. Overfilling with oil could indeed interfere with the performance of the refrigerant, hampering its capacity to withdraw and dispel heat. To verify, you'd need to check the high side pressure and compare it with the manufacturer's recommended settings.
Properly diagnosing an A/C system requires correct pressure readings. Typically, you should see high side pressure of around 150-250 psi (higher in hotter weather) and low side pressure around 20-30 psi in a properly filled and functioning system. Overfilled systems would likely show high pressure on both sides due to reduced cooling capacity.
In conclusion, your best course of action to address the issue would be to consider having the A/C compressor inspected, possibly replaced if it is determined to be faulty or excessively worn, and ensure the system is correctly filled with refrigerant and oil. Consult with a professional mechanic or a qualified HVAC technician for accurate diagnosis and repairs.Click to see AI response
I experienced this once on another vehicle that I owned. Apparently the person that owned it before me sold it to me with a "recent recharge". The reason that the compressor was locked up and the belt slipping was that when I put the gauges on the system to check the readings showed that it was way overcharged. Took out some R-134a and all was fine. IIRC it only takes about 2 cans of R-134a to be recharged to full. That might be the problem.
------------------ " THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite. "THE COLUSSUS" 87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H " ON THE LOOSE WITHOUT THE JUICE "
AeroDon had a solution for the unfixable squeal. Being a service tech for a diesel fleet, he found that a Freightliner belt solved the problem. It was a little meatier and filled the V groove of the pulley, giving it more contact surface. It didn't sit down into the pulley because it was thicker. Stock Goodyear number is 15730 for reference. It may be different on engine swaps.
IIRC it only takes about 2 cans of R-134a to be recharged to full. That might be the problem.
R-134A cans are typically sold as 12oz cans, which would make 2 can 24oz or 1.5lbs, which is way too little. The Fiero's original R-12 capacity is 40oz or 2.5lbs, typical R-134A conversions use 80-90% of the original R-12 charge, which would be about 2-2.25 lbs. Three 12oz cans is 2.25lbs, which is about perfect, since you're probably not quite going to get all of the 3rd can in.
R-134A cans are typically sold as 12oz cans, which would make 2 can 24oz or 1.5lbs, which is way too little. The Fiero's original R-12 capacity is 40oz or 2.5lbs, typical R-134A conversions use 80-90% of the original R-12 charge, which would be about 2-2.25 lbs. Three 12oz cans is 2.25lbs, which is about perfect, since you're probably not quite going to get all of the 3rd can in.
I certainly won't dispute those numbers but I've always recharged from the large commercial cylinders using gauges. Lets also remember that a full system recharge also uses about 6 oz of Ester oil
------------------ " THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite. "THE COLUSSUS" 87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H " ON THE LOOSE WITHOUT THE JUICE "
[This message has been edited by Dennis LaGrua (edited 09-08-2023).]
AeroDon had a solution for the unfixable squeal. Being a service tech for a diesel fleet, he found that a Freightliner belt solved the problem. It was a little meatier and filled the V groove of the pulley, giving it more contact surface. It didn't sit down into the pulley because it was thicker. Stock Goodyear number is 15730 for reference. It may be different on engine swaps.
I would be interested in this belt, that's something I was mulling, there's are 35 plus year old cars, those V-Groove pullies wear out, a thicker belt just may be the ticket.
R-134A cans are typically sold as 12oz cans, which would make 2 can 24oz or 1.5lbs, which is way too little. The Fiero's original R-12 capacity is 40oz or 2.5lbs, typical R-134A conversions use 80-90% of the original R-12 charge, which would be about 2-2.25 lbs. Three 12oz cans is 2.25lbs, which is about perfect, since you're probably not quite going to get all of the 3rd can in.
Man, I had 2.25 lbs of R134A put into my conversion with a new 3800 compressor, evacuated old ass stock system and that sucker blows so cold on Norm that I turn it down. Thank you for your knowledge^^
jelly2m8, if you have an old belt and can find a diesel repair shop, they might be able to match it up. I thought I had one in the garage, but not. Don had said there was a slight difference in length or the thickness of the belt made it a little difficult to get onto the pulleys. That was for a 60 degree engine setup. The same belt might not work on an engine swap.
That's a great suggestion, there's a few truck centers here I use for different parts. No the belt won't work for my application but I do still work on others and I have a customer who has an AC belt squeal with one of the popular automatic belt tensioners sold on the forum and my thought is his pulleys are simply worn, a thicker belt should fix his issue.
I came here to ask if any one has ever seen this on their A/C? I replaced all my switches parts etc but this was soldered into my old power supply. do I need this? I am sure RWD knows, he has been a massive help in his posts about A/C.
I came here to ask if any one has ever seen this on their A/C? I replaced all my switches parts etc but this was soldered into my old power supply. do I need this? I am sure RWD knows, he has been a massive help in his posts about A/C.
Yes, it is required for the plug. All Fiero's have them. It does look out of place though for sure.
AeroDon had a solution for the unfixable squeal. Being a service tech for a diesel fleet, he found that a Freightliner belt solved the problem. It was a little meatier and filled the V groove of the pulley, giving it more contact surface. It didn't sit down into the pulley because it was thicker. Stock Goodyear number is 15730 for reference. It may be different on engine swaps.
I was going to look into that. It appears that a couple of numbers got transposed. It should be a 15370. 37" sounds about right, since the stock belt is 37", according to the 22P. The number given was for a 73" belt. That... just didn't sound right.
Originally posted by 88TTops: I came here to ask if any one has ever seen this on their A/C? I replaced all my switches parts etc but this was soldered into my old power supply. do I need this?
CLICK FOR FULL SIZE
I am sure RWD knows, he has been a massive help in his posts about A/C.
Yes that is Required. All GM and many other have same Diode there to Stop Power Surges when the coil is turn off.
Dorman & others sell pigtail w/ the Diode. Must be installed right or Diode blows & car will have problems.
------------------ Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should. (Jurassic Park)
Steve, sorry about the transposition. Glad you got it figured out.
Not a big deal. Thanks for the tip. I appreciate it. Seems like I remember Don talking about that. But I've slept a few times since then, so...
My new belt just arrived this afternoon, so I'll report back in, one way or the other. Probably in a few days. Have some farm equipment repairs to get out of the way, first.
[This message has been edited by Raydar (edited 09-11-2023).]
ointer;" onclick="document.getElementById('HIDDEN84984').style.display='';document.getElementById('SHOWHIDDEN84984').style.display='none'"><!-- HIDE_CAPTIONSTART -->Click to see AI response<!-- HIDE_CAPTIONEND --></span>
. They were in a rush on the weekend to get the a/c working and shops weren't open to capture.
