Air conditioning rant and a few questions

ToddA1

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Joined
Aug 3, 2011
Location
NJ 08002
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'96 B4V, '97 B4 (sold), '97 Jetta (scrapped)
I finally decided to do something about my abysmal air conditioning on my B4V, due to tomorrow's 90° forecast. Easy enough, right? The car that I bought, last year, just for functional air conditioning...




Went to Autozone Friday night and picked up a flush kit, manifold gauge set, vacuum pump, PAG 46, and 2 o-ring kits. Saturday morning, I hook up the gauge set and the port connections are defective. I need to push and hold them to have the pins depress the port valves. Screw it, I know the system works somewhat and it holds pressure, I don't need to see the actual pressures. I'll go back when I'm ready to charge the system.

I decide to pull everything apart to start flushing. Everything is coming apart easily and I'm making good time. I encounter one bolt that's stripped and it's probably the toughest one to get to. It's the lower 4mm allen bolt on the TXV, tucked up nicely under the rain tray. I'm not willing to pull the dash to get the parts on a bench.

I cut a slot in the head making a flathead screw... no luck. I can't drill the head off because the slot, so I grind the entire head off. Still can't get it off because of the corrosion... I'm sure it's along the entire bolt. I end up breaking a screwdriver trying to pry the clamp away from the TXV. I finally decide to use a rotary tool to cut along the bolt, front to back. I end up burning out a newer B&D rotary tool. I go back with a die grinder and cut off wheel. After cutting, I'm finally able to separate the parts. I lost close to 2 hours on this...






I spend a few hours flushing all the parts and decide to run back to Autozone to exchange the gauge set. I had to go to a couple before I found one in stock. I keep flushing and start hooking everything up before quitting for the night.

Today, I'm pulling vacuum (30 minutes) by early afternoon; shut it down and it holds 30hg for over an hour. I decide to continue the deep vacuum while I replace the front end... maybe another 1.5 hours.

Off topic, but I also decided to clean out the intercooler since I had easy access. This is how I dried it out. I let the blower run on 3/4 throttle for about 30 minutes.




The car is back together and I start charging. The pedal is propped to 1200 rpm. 75°F ambient temperature, a/c is set to max and recirculate; the vents are putting out a steady 50°F during the charge, but after the last can is empty, the temperature rises to 52°.

I used 4 (12 oz.) cans, because I couldn't figure out a good way to determine how much freon I was adding. Every time I disconnected a can, it wasn't 100% empty, although it felt like it was. I was also losing freon when I was purging the charge line. I guessed that 2 oz was lost with each can swap/purge.

The low side eventually stabilized to 26 lbs, but the high side read 105 lbs. I can't find anything via Google regarding a low high side port pressure, so I'm thinking the gauge set is defective. I'll get another gauge set and verify.

I remove the low side quick connect, then the high side. A geyser of freon and oil erupt from the high side and I can't get it to stop... the valve is stuck open! F*CK, I just lost about 15 hours in time and $60 in freon and oil. I put the port caps back on, and go get fuel.

I really don't want to go through the ordeal of flushing everything again. OK, now the questions:

  • How do you determine freon weight when using individual cans?
  • Any ideas on the low, high side pressure? The compressor has yellow writing on it, like it's a junkyard part. Think it's going out?
  • Should the vent temperature have been lower considering the 75° ambient temperature? I was hoping to see low to mid 40°s.
  • I plan on swapping the port valves, deep vacuuming and recharging. How do I determine how much oil was lost? I was planning on adding a couple more ounces. Is too much oil a bad thing?
  • I'm thinking the drier will still be in a sealed system, so it won't need to be replaced... opinions?
-Todd
 

TonyJetta

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Joined
Sep 15, 2005
Location
Tucson, Az
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'15 Jetta TDI SE / '06 Jetta TDI DSG Pkg0 / '96 Passat TDI
I used 4 (12 oz.) cans, because I couldn't figure out a good way to determine how much freon I was adding.
That's about 1 can too much. You should be 41oz ±2oz / 1150gram ±50 gram.

I was also losing freon when I was purging the charge line. I guessed that 2 oz was lost with each can swap/purge.
Not even close. You might lose ~1gram (0.05oz) when purging that way.

The low side eventually stabilized to 26 lbs, but the high side read 105 lbs.
Your vent temps aren't unusual, and your low side temp is right on. But, your high side temp was too low. It should oscillate between 200 and ~250. This could be an artifact of overcharging.

...I'm thinking the gauge set is defective. I'll get another gauge set and verify.
I don't think your gauges are off. When the manifold is open to atmosphere, do they both read 0? To they have an adjustment screw on the face, with an access plug on the plastic cover?

I've had my Autozone gauge set for 4 years, and no issues.

I remove the low side quick connect, then the high side. A geyser of freon and oil erupt from the high side and I can't get it to stop... the valve is stuck open! F*CK, I just lost about 15 hours in time and $60 in freon and oil. I put the port caps back on, and go get fuel.
I would get the valve replaced ASAP! Otherwise you will likely need another drier/accumulator.

You didn't really lose 15hrs; maybe 2-3hrs. ;)

I really don't want to go through the ordeal of flushing everything again. OK, now the questions:

  • How do you determine freon weight when using individual cans?

  • Buy a small food scale. $10 or so.
    • I have a digital one I use, just for AC work.
  • Measure the can, full, empty, and with the valve on.
    • The nameplate weight on the can is usually about right on.
  • As you add the 1st 3 cans, total the weight of freon: 340+340+340 gram=1020 gram
    • Purge the line between each can.
  • Write down the full can weight, WITH the valve attached.
  • Slowly add freon from the 4th can.
    • Take your time and measure the weight.
    • Subtract the present weight from the total weight, you measured above.
    • You want to add ~130gram form the 4th can.
  • Keep in mind, you have a 50 gram tolerance. So, being a little low is not necessarily bad. i.e. the amount of freon you lose during a purge is not going to matter too much.

  • Any ideas on the low, high side pressure? The compressor has yellow writing on it, like it's a junkyard part. Think it's going out?
It might be. If the high side pressure was that low, it certainly could be on it's way out. Usually a failing compressor will have trouble keep the low side pressure that low.

OTOH, the control valve inside the compressor could be on it's way out. I have read that some people have replaced them successfully.

Low side: ~30psi
High Side 200-250 psi, depending on ambient temperature and level of charge.
At 75F...When the high side gets up to 250psi, the cooling fans should switch to high speed, and the high side pressure should fall back to 200-210psi, then the fans will slow down to the low speed.

  • Should the vent temperature have been lower considering the 75° ambient temperature? I was hoping to see low to mid 40°s.
That all depends on your blower speed.

At 75F-90F, my center vent temp will stay at 50-52F, when the blower is on high speed.
On speed 3: ~45-48F
On speed 2: ~43-46F
On speed 1: ~39-43F

This has to do with the amount of time the air has, to transfer heat from the evaporator core.

  • I plan on swapping the port valves, deep vacuuming and recharging. How do I determine how much oil was lost? I was planning on adding a couple more ounces. Is too much oil a bad thing?
That's hard to judge.

Adding 2 more ounces won't be bad. How much oil did you add in the beginning? The system call for 4.5oz.


  • I'm thinking the drier will still be in a sealed system, so it won't need to be replaced... opinions?
Because the screw on caps are not really sealed, this all depends on time. The longer the system is not sealed, the more likely you are to need a new drier.

Tony
 

ToddA1

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'96 B4V, '97 B4 (sold), '97 Jetta (scrapped)
Removed the port cap before I left for work, and it was still quietly hissing. Coming back from lunch the vent temp was 56° on high with an ambient temp of 87°. I got as low as 45° on speed 2.

Grabbed a service port kit from Autozone. MT-2907 contains both service ports with valves installed, 2 extra schraeder valves and the caps for about $10.

Got home late and started running around for 2 more cans of 134a. 2 Walmarts and 2 Autozones later, I gave up. Everything they had on the shelves had leak sealer and dye in it. I did grab a digital kitchen scale at Walmart for $20. Good idea... I was trying to do tare readings and can weight (with the valve) using a digital fish scale, lol. It wasn't working out too well.

I had to use vice grips on the valve. It wasn't metric or standard... likely a funky hvac service socket. Oiled the o-ring and installed with an adjustable wrench. I left the low side alone, being that the valves are AL and I didn't want to open another can of worms. When I pulled the high service port I added about 1.25 oz of oil with a syringe. In the beginning, I added roughly 4.5 to 5 oz. the measuring cup increments jumped by 4ozs, so I divided those and scratched marks on the cup.

Pulled vacuum for 40 minutes and it held 29hg for 40 minutes. I'll leave it in vacuum until I find more 134a.

The gauges are able to be set. They both zero out when disconnected. They both showed the same 100 lbs static pressure. Being that I couldn't find anything on the low, high port pressure, faulty gauges we're a thought. Figured if overcharging were a cause, it'd have been mentioned somewhere.

I figured 15 hours with all the disassembly and problems. If I wanted to pull the car apart and flush everything again, I guess it'd be a full 8 hour day with reassembly and recharge.

Thanks for the detailed reply!

I'm actually considering running some propane in the system to see the results. Been doing a lot of reading on the subject for a very long time. Supposedly all these green r12/134a substitutes are propane, butane or a mixture of both. Supposedly more efficient than r12 and r134a. You use less, too. 5 oz of propane is equal to 13 oz of 134a. I figure I'd need around 16 oz of propane.

If my compressor is on the way out, now is the time to try it out. Most compressor warranties are void if you use these substitutes.

The cost would be a charge hose to cut. I have plenty of propane, but I can get a 32 oz bottle for about $2.50.

-Todd
 

TonyJetta

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Keep us posted on how it works.

My 2 cents....While propane may sound like a cheap 'green' alternative to R134, I don't advocate it's use. Mostly because of the flammability aspect. And the fact that the system was originally designed for R134.

Tony
 

compu_85

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... None :S
Ya, with the variable displacement compressor, which varies based on pressure, you want to stick with 134a. Plus 134a cools great in these cars.

-J
 

ToddA1

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'96 B4V, '97 B4 (sold), '97 Jetta (scrapped)
Ya, with the variable displacement compressor, which varies based on pressure, you want to stick with 134a. Plus 134a cools great in these cars.
Not quite sure what a variable displacement compressor actually is or does, so I guess more research is in order.

If I can get 35% better cooling using a different hydrocarbon, I will. All the things that I've been reading for close to a year really have my interest piqued. The wagon is a big car with a lot of glass. Even when my vents were blowing 47° on that 87° day, the left side of my body was definitely feeling the sun. When it gets to be 100°, I'm sure I'll want colder vent temps than 134a can deliver.

Last night I ran around and got some stuff to try the propane. I bought:

  • a 14.1 oz cylinder for $3
  • a couple male/male barbs (only needed one) for $6
  • FI hose clamps $2
  • 2' of 0.25" ID hose for $3.
  • I had an old ac recharge hose and a propane nozzle. So they were no cost.
Total cost so far is about $14.

I went to Duracool's site to verify my conversion and I was correct @ 16 oz. for a 40 oz. system. Duracool is mostly propane and butane. The camping fuel that I saw at Walmart was a mix of propane and butane. It looked like an Acme thread on the can, but that would have been too easy... it wasn't. I wasn't looking to buy a camping stove to rob it of the fitting, so I stuck with propane.

Last night I put the gauges on the car and the vacuum dropped to 25" hg, so I deep vacuumed for another hour. Tonight, I hooked the gauges back up and I still read 29", so I was satisfied. Time to start the charge. Ambient temperature is 55°, not exactly ideal.

The cylinder with my charging rig weighed 38.9 oz. I ended up getting about 12.5 oz. in, and that would convert to about 31.25 oz. of 134a. I put the gauge set back on and saw static pressure at 104/100 lbs.

I start the car and I hear the clutch kick in. Air blows frigid for about 10 seconds; my digital thermometer wasn't fast enough to read the lowest it blew. The lowest I saw was 47° and then it started climbing; I saw it stabilize around 62°. What I noticed was the low side hose got cold for only about 10 seconds then warmed up. When blowing cold, the low side would read about 27 lbs. and I'd see the high side creep up to around 150 lbs. These pressures are pretty typical for propane. Apparently the gauge set isn't defective.

When the system stopped cooling (10 seconds later) the low side would remain the same but the high side would go back to 100 lbs., the same issue that I was having when running 134a. I'm guessing I wasn't paying attention when the high side was climbing, but the system never stopped cooling and it was a much warmer day. This happened a few times before I got frustrated and cleaned up.

I realize that the system is undercharged, but I'd think that it would be able to keep a consistent temperature that's below ambient. I'll get that last 3.5 oz. in there later.

Tony mentioned that this could have been an artifact due to me overcharging, but now I'm seeing the same issue with undercharging. I'll research the control valve that he mentioned.

If I end up having to get a new compressor, I'll have to stick with 134a to satisfy the warranty, although I'm not sure how they'd know.

-Todd
 

ToddA1

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I got back on this tonight with the hopes of wrapping it up. Hooked the gauge set to the car and started it up. Once again frigid air, but this time it didn't turn off after 10 seconds. Not sure what's happening, but I'm not asking questions.

Grab the vent thermometer and it's reading around 50° @ 900 RPM with an ambient temperature of 70°. That's basically where I was at with 134a, but with a 1,200 RPM and a 75° ambient. I guess it's not too bad considering that I'm undercharged.

I read somewhere that propane doesn't really shine at idle. Where you'll see the most cooling is at cruising RPMs, so I take it it to 1750 RPM and see 37°! It could have dropped lower, but I got excited and decided to put the last 3.5 oz. in. Disconnect the low side and a geyser of propane erupts from the service port.... great. Put the gauge set back on, and remove the low side again and it stops. I'll deal with it later.

So, I owed the system 3.5 oz. and I factor I lost at least 2 oz. with the newest port leak (I started wondering how much refrigerant the manifold gauge set held). I decide to put 5 oz. in. These are my results @ 70° ambient:

  • 900 RPM----> 49.8°---> 30/180 port pressure
  • 1750 RPM---> 39.3°---> 24-27/210-220 port pressure





I never saw the 37° again, and I may have slightly overcharged the system. I've read that propane works better when slightly undercharged. I can bleed some out later and see what happens.

I left the air running while I was disconnecting and packing up. I go back to the car and now the vents are reading 65°. I'll have to do some research on what could cause this. I'm not sure if the reed valves in the compressor would cause intermittent compressor failure. If so, time for a new compressor.

I'm thinking the fluctuations that I'm seeing on the 2nd reading may be the control valve going out as Tony mentioned, but I don't know if it would cause an intermittent issue. It's purpose is to bleed high side pressure to the low side when the low side is too low. It's a fairly cheap part, and it's a lot cheaper than a compressor.

Feeling around the compressor, it feels like the control valve may be on the underside. Anybody know for sure?

-Todd
 

ToddA1

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'96 B4V, '97 B4 (sold), '97 Jetta (scrapped)
Any ideas about the low high side readings?

From what I've read, the control valve would show higher than normal low side pressure when faulty. IIRC, it can be bypassed with a nut and bolt, but then another hi/low switch would need to be added.

A faulty TXV would show both pressures to be either high or low, in unison.

The current hi/low switch wouldn't have anything to do with my issue, other than shutting the compressor down, which would then show equal static pressures. I'm out of things to research.

At this point, I'm leaning towards the compressor. Would bad reed valves give me an intermitant issue? I can sometimes turn the AC off, wait a few minutes and it'll start working fine again, then it'll go warm again. I've seen a breakdown of this compressor and the reed valves look like thin shims of starfish shaped metal or some other type of composite material

I don't want to fix the problem by throwing expensive parts at the car, so this point, I think I'll look for a used compressor. The SD7V16 was used in VWs up to 2005. I figure a 7 y/o compressor is better than my 15 y/o compressor, and the junkyard will give me a warranty of at least 30 days.

It seems the 2 differences between the compressors after 2002 is the pulley is 7 groove instead of 6 groove, but i'm not even sure that would matter... I may just have an empty groove when using my 6 rib belt. The other issue would be a different connector for the clutch coil. Both of these would be simple fixes, if I wanted/needed to swap pullies and clutches.

Any other ideas before I go junkyard hunting?

-Todd
 

TonyJetta

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'15 Jetta TDI SE / '06 Jetta TDI DSG Pkg0 / '96 Passat TDI
lower high side pressures could also be the TXV not regulating temperature. Which would also coincide with the intermittent issue you are experiencing.

Th elast one I had would regulate the temp at about 50F on a hot (>100F) day. AC shop said it was fine. When I pulled it last month, there was an O-ring stuck on the outlet (evap) side of the liquid line.

They are cheap enough (~$70, IIRC), to try replacing. And, yes, even new ones will fail-on-install.

Tony
 

ToddA1

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lower high side pressures could also be the TXV not regulating temperature. Which would also coincide with the intermittent issue you are experiencing.
True; I was initially looking toward the TXV, until I did more research. I guess it's cheap enough to replace, so when I purge the system, I'll remove and inspect.

What turned me away from the TXV is when the valve sticks closed the high side drops and the low side would also drop. In this case, such a dramatic drop should put the low side in vacuum, according to what I read.

What I may do is wait for another warm day pull the TXV cover and turn the air on. I've heard that tapping on it can get the TXV to free itself if it is sticking open or closed.

Called a local junkyard and they'd want $25 with afor a compressor, so that's definitely not terrible, especially if I find a later one.

Thanks for the reply. It seems that you're the forum's AC guru.

-Todd

BTW, this past Saturday we had an 80° ambient temperature. I saw 32° vent temps. It's been in the 60s since, so there hasn't been a need to turn the AC on.
 

TonyJetta

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Thanks for the reply. It seems that you're the forum's AC guru.
Thanks for the kind words.

I don't know about AC guru, though. Just a little too experienced with B4 AC system over the last 4 years.:rolleyes:

Tony
 

ToddA1

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Haha. I wish I could be blissfully ignorant on the subject, too.

-Todd
 

ToddA1

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I joined an ac forum and basically cut and pasted my issue.

Someone brought up the control valve and I reiterated what read about higher than normal low value. This same person wrote an article about the valve and added that any odd pressure values could point at the valve. The later info wasn't in the article.

I've ordered a control valve, some DEC Pag 46, and some Nylog. There are 2 different gasket kits and lip seals for this compressor. The site that I ordered from said the only way to tell which you needed was to open the compressor, and look at them.

Autozone sells a Santech kit that includes the lip seal for $31, but of course it's a special order, but it's returnable. I'll be going in tomorrow am. Most sites only sell the kit that's geared to the earlier compressors, that I likely have. Many have said the gaskets come off in one piece, and are reusable. We shall see.

-Todd
 

ToddA1

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Tony,

Everything I ordered came from http://www.acsource.com/. With shipping, the valve, Nylog and DEC Pag was about the same price that Autozone wanted for the valve, alone.

That site also had the gasket kit. Their gaskets are fiber and it doesn't include the lip seal. It's likely that I have the earlier compressor, but can't be sure, since it was replaced. Being that I couldn't return anything kind of steered me away.

Although the SD7V16 isn't listed, this lip seal is one of the 2 that may fit our compressors. The other one isn't stocked.
http://www.acsource.com/shaftseal-lipsealsk-730nfitssd-709.aspx

The kit that I ordered from Autozone (MT-2199) has metal gaskets and it includes the lip seal. It worked out to be around the same price.

The above store is affiliated to the forums where I posted my thread.
http://acsource.net/acforum/viewtopic.php?f=1&t=10015

Here's the article that focused on the control valve. The author later told me that any erratic pressure values could be the valve. That part wasn't mentioned in the article.
http://www.aircondition.com/tech/qu...Could-Mean-A-Faulty-Refrigerant-Control-Valve

I was working with a HVAC tech at work, and we were discussing charging procedures. He told me I was crazy charging as a vapor. I usually charge under vacuum as a liquid through the high side, but finish off as a gas. I'll bleed it in slowly as a liquid through the low port from now on. I've also read that since our low side service port is so far away from the compressor, that slugging isn't really a huge concern as long as you're trickling in.

I also ended up ordering a set of service port sockets, online. I need to change the low port.

-Todd
 

ToddA1

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Everything that I ordered came in Wednesday. Time to do work. I pulled the compressor, drained the oil, and pulled it apart.




Pulled the control valve and I found this...




There's a reed valve missing an end! What kills me is that the valve or any metal chips aren't inside. I'm wondering if someone opened this thing and put it back together knowing about the issue.

There are some gashes where someone was digging an old gasket up or where the missing piece was bouncing around. It looks like it may have made it's way into other cylinders, as there are a few pistons with dinged crowns. There's also some weird corrosion happening on 2 pistons.




Oh well, I figured, I'd get another compressor and rob it of that reed valve assembly. Being a curious guy, I decide to pull the compressor totally apart to see what makes it tick. Grab a puller to pull the clutch and this happens...




At this point, I say "F*CK IT". I'm going to reassemble this thing with the old gasket, new control valve and see what happens. I have nothing to lose at this point and I can always pull that valve out if it doesn't work. I cut the mushroomed end shaft off and Locktite the nut back on.

Refilled the compressor with slightly more DEC Pag than came out. Pulled deep vacuum for 1.5 hours and it's sitting right now.

-Todd
 

TonyJetta

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Todd,
Thanks for the poics. I, too, have been curious about the inner working of the SD7V16 compressor. I have the old one off my B4, that I replaced back in March. If I get curious enough, I'll tear it apart sometime.

Tony
 

ToddA1

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Aug 3, 2011
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NJ 08002
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'96 B4V, '97 B4 (sold), '97 Jetta (scrapped)
Tony, I wish I weren't so curious and willing to learn, lol. It would be so much easier to play ignorant and pay a shop.

I decided to charge it tonight. Bought a twin pack of propane for less than $5.50 from Target. How perfect is it that each cylinder is 16.1 oz. A perfect fill. Charged as a liquid and finished in about 20 minutes.

70° ambient temperature and I finally see normal pressures of 25/225 @ idle and 25-30/240 @ 2,000 rpm. Occasionally the low rose as high as 40, but it settled back down quickly.... cooling never stopped.

Fan is set to max and recirculate. Temperature @ idle is only 51°. Temperature @ 2,000 drops as low as 33°. Not great being that I saw 32° on a 85° day.

20 minutes later, I lose cooling. Get it back in the driveway and hook up the gauges. Low is at 110 and high is at 150; the clutch is still engaged. Turn off the ac, wait 3 seconds and turn it back on.... cooling resumes, and pressures return to normal.

At this point, I know I have a broken reed valve and that can't be helping. I'm thinking tear a compressor open at the junkyard to verify reed valve condition and swap good parts into my compressor. I'm this far into it, so why not? It'll cost me less than $6, factoring the oil and propane. My labor is free.

-Todd
 

TonyJetta

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Sep 15, 2005
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'15 Jetta TDI SE / '06 Jetta TDI DSG Pkg0 / '96 Passat TDI
Todd,
I agree that the broken reed is not helping your situation.

If you can pick up a 'newer' reed plate for $6 or so, and don't mind putting the time into it, I'd go for it.

Tony
 

ToddA1

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NJ 08002
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'96 B4V, '97 B4 (sold), '97 Jetta (scrapped)
I did a junkyard run today and pulled a compressor from a 95 Jetta 2.0. Opened the compressor and black oil poured out. This compressor was overheated to the point that the gasket coatings were bubbling off. Moisture also made its way into the system, but the part that I needed was good. I took the entire reed valve plate.




Cleaned up the suction reed valve and compared it to mine; a perfect match. Oddly enough, the discharge reed valve was different. I compared the plates and they were slightly different as well. My discharge reed valve and plate has larger ports. Discharge valve limiter was the same. I just needed the suction valve, so it got cleaned up and swapped into my compressor.

I couldnt figure out the strange wear mark at the center. The way it looks would mean the control valve was mounted off center, which it wasn't.




Currently pulling vacuum. Recharge happens tomorrow... fingers crossed.

-Todd
 

ToddA1

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NJ 08002
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'96 B4V, '97 B4 (sold), '97 Jetta (scrapped)
Bah! The AC was working perfectly with temps as low as 31° on the highway. I was giggling like a schoolgirl, then it kicked off. I thought the evaporator froze up but I jumped out, hooked up the gauges and saw the low pressure at around 90. It took about 30 minutes for this to happen... it lasted way longer than it ever has.

I'm guessing there's more wrong with my compressor than I had hoped.

-Todd
 

GTSLOW

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TDI
15 GSW & 04 Golf
Ugh any advice for a AC noob that bought my 96 Passat with non-working AC? I was honestly thinking of trying to take it to a shop and having them do the generic $40 AC recharge and cross my fingers.
 

ToddA1

Top Post Dawg
Joined
Aug 3, 2011
Location
NJ 08002
TDI
'96 B4V, '97 B4 (sold), '97 Jetta (scrapped)
I was honestly thinking of trying to take it to a shop and having them do the generic $40 AC recharge and cross my fingers.
If you can get it done for that price, why wait? You could try one of the cans with gauge jobs that you see on the shelves. You may just be low on refrigerant.


I buy compressors for about 200 bucks sounds like u should go this route.
I'm guessing they're the China compressors that I see all over eBay? What's your long term experience with them?

I'm now wondering if the newly replaced 4 Seasons TXV could be faulty.

-Todd
 

GTSLOW

Veteran Member
Joined
Oct 26, 2010
Location
Fort Knox, Kentucky
TDI
15 GSW & 04 Golf
If you can get it done for that price, why wait? You could try one of the cans with gauge jobs that you see on the shelves. You may just be low on refrigerant.

-Todd
My question is and I think I've heard this mentioned before. If I'm low on refrigerant would that keep the compressor from kicking on? Reason I ask is when I hit the AC button nothing really happens with the engine. Would low refrigerant cause the pump to not work?
 
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ToddA1

Top Post Dawg
Joined
Aug 3, 2011
Location
NJ 08002
TDI
'96 B4V, '97 B4 (sold), '97 Jetta (scrapped)
Yes. The compressor needs to see somewhere around 15lbs as a fail safe. You can jump the pins at the low pressure cut off switch and see if the clutch engages. If it kicks on, you're likely low. I wouldnt run it like that for long... it's just a test.

-Todd
 

GTSLOW

Veteran Member
Joined
Oct 26, 2010
Location
Fort Knox, Kentucky
TDI
15 GSW & 04 Golf
Very good thank you Todd!! I didn't want to spend $160 on a "AC Diagnose/Test" only to have it come back as needing a charge.
 

KLXD

Top Post Dawg
Joined
Aug 22, 2009
Location
Lompoc, CA
TDI
'98, '2 Jettas
Three bucks per can for refrigerant????

The best I can find it here in Kal it $12 plus $10 deposit per can. Also there's a time limit on the deposit so if you use a half can you either loose the deposit or the product. I'm tempted to vent it just for spite, then return the can.

Regarding the Chinese pumps, after talking to the guy at AMA I bought one. He said they weren't having problems with them. Mine lasted less than a week then seized. I paid the extra for a Sanden rather than get another CRAP replacement under the warranty. It's been going strong for months so I guess it wasn't my installation.
 
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