AC not coolingÂ Pages: 12

Boomer_106 on Tue May 12, 2009 1:16 PM

Year: 88
Make: Chevy
Model: Iroc-Z
Engine Size: 5.7
Refrigerant Type: R-12
Ambient Temp: 66
Pressure Low: 45
Pressure High: 110
Country of Origin: United States

I finally received my high side adapter from AMA and can now take readings. I am using Mastercool gauges also from AMA Part no 66773. Just for your info, I also have a Mastercool leak detector kit (haven't used it yet) Part 53351 and an electronic leak detector, blue point ACT 725. Mastercool vacuum pump 90059. Now you know what tools I have at my disposal. I currently have 1 can of R-12 available. 14oz I believe. I have a DVD from autozone on doing AC made by Bruce Bonebrake. It tells me to take the first reading with the engine off so I did.

Engine off
Low side=45
High side=34

Engine running for about 10 Minutes
Ambient Temp 66*
Vent temp 70*
Idle 800 RPM
AC on max, fan on high
Low side= 45
High side= 110

After taking the above engine on readings and shutting the engine off
Low side=58
High side=50
Just trying to provide all the info I can.

I'm pretty certain this indicates low on refrigerant. Question is does it have enough for me to add uv dye or, do I need to charge before adding dye?

Edited: Tue May 12, 2009 at 1:42 PM by Boomer_106

Dougflas on Tue May 12, 2009 3:50 PM

You can add your dye now. Give us the pressure readings with the doors open, engine at 1500 rpm, ac set to max high speed blower.

Boomer_106 on Tue May 12, 2009 5:00 PM

Quote
Originally posted by: Dougflas
You can add your dye now. Give us the pressure readings with the doors open, engine at 1500 rpm, ac set to max high speed blower.

Doors open
1500 RPM
ac max high blower
Low side= 45
High side after about 5 minutes was 110. Running for another 5 min or so it had fallen to 80.

The clutch really short cycles in this thing. 1 sec on about 3 sec off. Is this normal?

Chick on Tue May 12, 2009 5:21 PM

You appear to undercharged.. High side should be around 2.2 to 2.5 times ambient if you're not going to evac/charge, and just top off.. Charge until the outlet of the evaporator is the same temp as the inlet.. However, it's best to do when the ambient is at least 70 to 75 degrees...

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Chick
Email: Chick

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Freedoms just another word for nothing left to lose

Edited: Tue May 12, 2009 at 5:22 PM by Chick

mk378 on Tue May 12, 2009 5:30 PM

This is all normal for being badly undercharged. Start sniffing for leaks. The compressor shaft seal is prone to leak on GMs. You can take the belt off and put a bag over the front of the compressor to collect the R-12 that leaks out, making it easier to detect.

Boomer_106 on Tue May 12, 2009 8:08 PM

Quote
Originally posted by: mk378
This is all normal for being badly undercharged. Start sniffing for leaks. The compressor shaft seal is prone to leak on GMs. You can take the belt off and put a bag over the front of the compressor to collect the R-12 that leaks out, making it easier to detect.

I put the bag over it leaving the belt on. The detector did go off. I added dye to the system and didn't see anything. Maybe there isn't enough refrigerant to carry the dye through the system? I hate to just start replacing a seal without good confirmation that it's the problem. See my next paragraph

Here's the thing, on my 92 S10 pickup, for the heck of it, I put a bag over that for a little bit and, it also set the detector off. I have never had to recharge the truck. I've had the truck for 13 or 14 years. I haven't tried the AC this year but, it worked last summer. I was going to check the pressures on it just for the heck of it but, apparently it takes a different high side adapter than the 88 Iroc? I hate these automakers.

What do you guys suggest I do next?

Boomer_106 on Tue May 12, 2009 8:11 PM

Quote
Originally posted by: Chick
You appear to undercharged.. High side should be around 2.2 to 2.5 times ambient if you're not going to evac/charge, and just top off.. Charge until the outlet of the evaporator is the same temp as the inlet.. However, it's best to do when the ambient is at least 70 to 75 degrees...

Chick you guided me to that high side adapter in a different thread. It appears my 92 S10 uses a different one than the 88 IROC? Ridiculous. Can you tell me which one the 92 S10 needs? Thanks to everyone that has replied.

Dougflas on Tue May 12, 2009 10:03 PM

On your 88, the dye will have to circulate thru the system. You'll need to charge it up and run it for the dye to indicate. If your electronic detector goes off on the low range, you most likely have a leak. Recover the charge and replace the seal.

Dougflas on Tue May 12, 2009 10:09 PM

For your 92, this is probably the adaptor you need.

https://www.ackits.com/pc/90338/chargeadapter/90338+-+Service+Port+Adapter

Boomer_106 on Tue May 12, 2009 11:56 PM

Quote
Originally posted by: Dougflas
For your 92, this is probably the adaptor you need.

https://www.ackits.com/pc/90338/chargeadapter/90338+-+Service+Port+Adapter

I think you're right about that adapter because the 92 did have the recessed valve core.

GM Tech on Wed May 13, 2009 8:47 AM

Those were known durring the day - casually as "Deep Throat" valves... Same time period as the movie I believe..

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The number one A/C diagnostic tool there is- is to know how much refrigerant is in the system- this can only be done by recovering and weighing the refrigerant!!
Just a thought.... 65% of A/C failures in my 3200 car diagnostic database (GM vehicles) are due to loss of refrigerant due to a leak......

Boomer_106 on Wed May 13, 2009 10:29 AM

So GMTech, do you second Dougflas recommendation of changing the seal at this point or, can I do some further testing to make sure or, what? Also if I have to change the seal, should I just go ahead and convert to 134a since I have to empty the system? What about some people I have heard experiencing less cooling after conversion? If I convert, I assume I would have to thoroughly flush the entire system? This would be alot of added labor it seems. I don't have a flush kit either.

GM Tech on Wed May 13, 2009 11:13 AM

If you want to test more- then pull the clutch driver off- can be done without dismounting compressor-no need to discharge either- and let your sniffer lay inside the snout, by the shaft-when I do this, the sniffer will sound about every ten minutes or so- Shaft seals can burp- not a continuous leak- so just be patient- walk away- and you will hear sniffer sound off for each burp..-also look for the oily/greasy build-up inside the snout- a no-doubter for a shaft seal leaker. Also the drive plate surface and the pulley face surface will be covered in oil/grease- certainly not dry. Below is a worst case scenario.

I always stay with original refrigerants- never convert- easier for me since I have stock piles of R-12. Just don't want the hassle - plus R-4 compressors and 134a are a really bad combination IMO- just look at all the 94-95 C/K & S/T truck compressor changes....there were tons that failed due to lack of lubrication. Why go through all the hassle of conversion, when R-12 is readily available. Any shop will tell you anything to get you to convert, because they typically only carry 134a. Same is true with Dexcool- they don't wish to stock multiple coolants or refrigerants- but will convince you it is in your best interest to do it their way...

-------------------------
The number one A/C diagnostic tool there is- is to know how much refrigerant is in the system- this can only be done by recovering and weighing the refrigerant!!
Just a thought.... 65% of A/C failures in my 3200 car diagnostic database (GM vehicles) are due to loss of refrigerant due to a leak......

Edited: Wed May 13, 2009 at 11:31 AM by GM Tech

Boomer_106 on Wed May 13, 2009 12:30 PM

That sounds like a good idea. Can't hurt. I wish I had enough to carry that dye through the system but, it doesn't look like that is gonna happen. Now I've read the post in the tips forum about changing your shaft seal made by chick with a contribution from you as well. Of course the automakers have to make the special tools different from some compressors to others. The service manual tells me I need a J-33013-B Hub and clutch drive plate assembly remover. When I google this I find references to the tools but, not the tool itself. How can I find the tools I need for this vehicle? The service manual shows a ton of tools for compressor work. For example, removing the nut J-25030 clutch hub holding tool. Hub and drive plate installer J-9480-B. Seal remover and installer J-23128-A. Shaft seal protector J-34614. Clutch coil puller J-25287. Seal seat O ring installer J-33011. Rotor bearing remover J-9398-A.

Thats just an example. There are a bunch of tools but, I think some are for complete compressor overhaul. How do I get the ones I need? Can I use a common tool in place of some of these special ones? Here is a pic of my compressor.

You can click that image for a larger image. If you have dial up you may not want to. It's huge. Ignore that stupid link below. I can't figure out how to edit it out.

http://www.largeimagehost.com/gallerys/untilted/QXshts.html

Edited: Wed May 13, 2009 at 1:04 PM by Automotive Air Conditioning Information Moderator

GM Tech on Wed May 13, 2009 12:47 PM

Borrow the necessary tools from Autozone- just need a clutch puller and pulley puller- and shaft seal puller

-------------------------
The number one A/C diagnostic tool there is- is to know how much refrigerant is in the system- this can only be done by recovering and weighing the refrigerant!!
Just a thought.... 65% of A/C failures in my 3200 car diagnostic database (GM vehicles) are due to loss of refrigerant due to a leak......

Boomer_106 on Wed May 13, 2009 1:00 PM

Quote
Originally posted by: GM Tech
Borrow the necessary tools from Autozone- just need a clutch puller and pulley puller- and shaft seal puller

Is that just to check what you said or, to replace the entire seal? What do I use in place to hold the clutch hub while pulling that nut off?

TRB on Wed May 13, 2009 1:02 PM

Edit works for me but not when I edit the post.

That sounds like a good idea. Can't hurt. I wish I had enough to carry that dye through the system but, it doesn't look like that is gonna happen. Now I've read the post in the tips forum about changing your shaft seal made by chick with a contribution from you as well. Of course the automakers have to make the special tools different from some compressors to others. The service manual tells me I need a J-33013-B Hub and clutch drive plate assembly remover. When I google this I find references to the tools but, not the tool itself. How can I find the tools I need for this vehicle? The service manual shows a ton of tools for compressor work. For example, removing the nut J-25030 clutch hub holding tool. Hub and drive plate installer J-9480-B. Seal remover and installer J-23128-A. Shaft seal protector J-34614. Clutch coil puller J-25287. Seal seat O ring installer J-33011. Rotor bearing remover J-9398-A.

Thats just an example. There are a bunch of tools but, I think some are for complete compressor overhaul. How do I get the ones I need? Can I use a common tool in place of some of these special ones? Here is a pic of my compressor.

You can click that image for a larger image. If you have dial up you may not want to. It's huge. Ignore that stupid link below. I can't figure out how to edit it out.

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When considering your next auto A/C purchase, please consider the site that supports you: ACkits.com
Contact: ACKits.com

Boomer_106 on Wed May 13, 2009 1:55 PM

Also it looks like the installer tools are different?

GM Tech on Wed May 13, 2009 2:27 PM

An impact gun will zip the nut off the shaft - no holder necessary- I don't use one ever.

The installer tool can be the same as the remover for the shaft seal and the clutch driver- you will need a shaft seal protector when slipping the seal over the shaft - but some have used shrink tubing over the shaft in lieu of buying the shaft seal protector tool.

The pulley installer tool can just be a large socket to tap the pulley on- as well as for tapping the coil on- just use common sense- always press/tap on the press fit race so not to damage the bearings...

-------------------------
The number one A/C diagnostic tool there is- is to know how much refrigerant is in the system- this can only be done by recovering and weighing the refrigerant!!
Just a thought.... 65% of A/C failures in my 3200 car diagnostic database (GM vehicles) are due to loss of refrigerant due to a leak......

Boomer_106 on Wed May 13, 2009 9:35 PM

Thanks, I think I'll start with just pulling the drive off and taking a look at what is in there. I'll sniff around like you said. I would think I would see at least some oily substance. Guess I better start watching ebay. I'm gonna need more R-12

Boomer_106 on Thu May 21, 2009 12:28 PM

Ok, I got the tools from autozone. I got two clutch hub removers. One is made by "factory air" model 59581. The other is brand "OEM" #27005. The problem is, neither one will thread into my GM compressor. Going by looks, I think they might be the same exact tool just different manufacturers. This is frustrating. How can they not have the tool for one of the most common compressors in the U.S? Do all GM R-4 compressors need the same remover or, did they make those different too? Anyone know what hub remover will work on this 88 IROC? I got the numbers from the service manual as I mentioned in this thread but, searching the net for those turns up nothing. I'm about ready to just charge it up and, see how long it takes to lose the refrigerant. I hate to throw away money like that on freon but, nothing is going my way here.

Boomer_106 on Fri May 22, 2009 2:04 PM

Anybody home?

HECAT on Fri May 22, 2009 2:23 PM

Yes, take the wrong tools back to Autozone (don't hit the kid behind the counter with them) and exchange for the correct ones. Their web site says OEM27005: Removes hubs on Warner replacement clutches for Ford FS6.

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HECAT: www.hecatinc.com You support the Forum when you consider www.ackits.com for your a/c parts.

FLUSHING TECHNICAL PAPER vs2.pdfÃÂ

Boomer_106 on Fri May 22, 2009 3:17 PM

Quote
Originally posted by: HECAT
Yes, take the wrong tools back to Autozone (don't hit the kid behind the counter with them) and exchange for the correct ones. Their web site says OEM27005: Removes hubs on Warner replacement clutches for Ford FS6.

Thing is I got all the removers they had. Now I don't know where to find the one I need. Should I find a kit that covers a bunch of vehicles? I still need to make sure it fits most GM if I do because all of my vehicles are Chevy. I'm starting to wonder how far I should go with buying tools as a DIYer

HECAT on Fri May 22, 2009 3:41 PM

I had a feeling they may have just given you the two they had. Chances are they do not even know what they are for.

I have followed a lot of posts regarding compressor seal service and it always boils down to the pro's saying it can be done but with all these special tools. The DIY tech then has to buy or borrow tools and change 3 leaking seals only to find out that the pro's had to go thru the same type of initial learning curve.

I have been in the automotive business for over 27 years (technical, sales, and now make tools). I do not own such tools or plan on purchasing. I am not saying it cannot be done, it can; but I personally would replace a leaking R4 if it was mine.

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