This automotive AC stuff is a PITA

[White Horseradish]

So, my AC saga continues.

I have learned that I am not as clever as I thought I was. GM bested me. The 1994 AC hoses that have the 134a fittings and the new rubber sections I was after have one small, but important difference. The 134a compressor manifolds not only have different size tubes, but one side of the manifold goes deeper into the compressor by about 1/8 inch. The R12 compressors have the ports at the same level. Also, the threading on the drier to evaporator connection is different. Anyhoo, I got all that stuff squared away with a new drier can and a junkyard compressor with the correct ports. I'm pretty sure it was not a leaky one. I put it all together with new o-rings and it holds vacuum overnight. So, I tried to put some pressure to it and discovered that the yard compressor had a weak clutch magnet. The relay would engage and the engine RPM would increase, but the clutch would only lock if I hit it with a b.f. wrench and then let go almost right away. Also, if I plugged the old compressor into the harness the clutch would lock on it.

So, I embarked on the fascinating journey of swapping compressor clutch magnets. The clutch design of Harrison compressors makes me want to administer canings to the engineers. Freaking everything is a press-fit requiring lots of messing with pullers and pushers. I suppose it makes sense for ease of mass production, but repairing it is very annoying. I have discovered a few things. One, is that no one auto parts store has a complete set of tools to replace an AC clutch. I had to get three tools at Autozone and one at O'Reilly.  Two, a lot the the so-called AC tools do not fit Harrison clutches used in Chevy pickups, no matter what the box says. Three, no one knows how to work on this stuff. People are just plain afraid. Four, the tools are mostly for pulling things apart. Putting things together requires creativity. I bet auto AC shops don't even screw with this and just send them out to rebuilders.

I am at the point where I have removed the working magnet from the old compressor. I will try to get it onto the installed compressor without pulling it because I don't want to vacuum this thing again.

Meanwhile, I decided to fix the AC on my wife's van, while I was at it. The guy I bought the van from said he had engine work done and system emptied, and then never bothered to get it refilled. He lied. There was a leak in one of the lines, and it cost me a charge of refrigerant to figure that out. The line in question is discontinued, so I had to go yarding to find one. Again, I happened onto a system that had pressure, so I knew line was good. Replaced line, vacuumed, then filled. The damn thing worked for two minutes, then spilled the entire oil charge. Actually, not so much spilled as tossed all over the place. Given the fine oil mist above the engine compartment and the neat straight line on the ground under the compressor pulley I'd say it's a safe bet the compressor shaft seal went. O'Reilly quoted me $239 and a few days wait for the compressor. FFFFFUUUUUUU....  evilBay  seems to have them for $80, so I will try that. The compressor is in a rather annoying spot and I don't want to get one from a yard just to have it blow on me in  short order.  Now I just need to decide if I want to replace the drier can at the same time or not.

I don't think I could come up with the cash to pay someone for this much screwing around.

[Monkeyleg]

I don't think I could come up with the cash to pay someone for this much screwing around.

I'd bet it would run $1200-$1500 or more.

[White Horseradish]

I'd bet it would run $1200-$1500 or more.

I paid less than that for each of the cars. 

[Tuco]

Meanwhile, I decided to fix the AC on my wife's van, while I was at it.

 
BTDT

Live and learn, my friend.
With personal vehicles, one at a time.
One at a time

[White Horseradish]

Live and learn, my friend.

This was definitely a learning experience. I have a bit more respect for the rates AC guys charge. I also am fairly sure I won't be buying their services, I can't afford it.

With personal vehicles, one at a time.
One at a time

I have spares. :D  Actually, I need to pare down the fleet. Ideally, I want to be left with a van for the wife, a station wagon for me, and a truck for emergencies.

[Bogie]

I think all the vehicles that are around me (but mine, because it hasn't been done yet...) have the same fittings... Same threading, all that fun stuff.
 
Taking a day off from the metal stuff, finishing a bunch of stuff tomorrow. May get a bit more time on the lathe tomorrow too.
 

[White Horseradish]

I think all the vehicles that are around me (but mine, because it hasn't been done yet...) have the same fittings... Same threading, all that fun stuff.

That might be a bad assumption. It's what screwed me up.

Take the Chevy pickup. I got a replacement drier can for it. The can looks right, fits in the mount. Except that between 92 and 94 they changed the threading on the female fitting of the can. It's the same size, different pitch.

[French G.]

My AC fix. My POS truck had no charge when  I bought it. Rotate vent window so it blows on me, drive fast. 5 years now, system works perfectly. 

[Nick1911]

[ Edited content ]

Might want to edit that out...

http://www.epa.gov/ozone/title6/608/faq.html#q2

[Monkeyleg]

I paid less than that for each of the cars.

Yeah, I had that problem with my beater '91 Saturn back in 2003 when the A/C went. The owner of the repair shop said the cost to replace the condenser and other parts was over $1000, and the car was worth maybe $600.

The car still runs fine, but it's hot as hell here in AL.

[zahc]

The AC on my Tahoe used to work but conked out this spring. I went to add a can to it, and when I loosened the plastic cap on the high side (it was an accident, I know you have to add the refrigerant to the low side) it hissed at me. This tells me that the fitting is bad, correct, because I presume the plastic cap is just a dust cap, and is not supposed to be holding any pressure, right?

Any way, I cranked the plastic cap down as tight as I dared and put a can in it and it works, kinda

Where do you get tools for working on AC? I understand that you need a vacuum pump, and gages.

[Nick1911]

Where do you get tools for working on AC? I understand that you need a vacuum pump, and gages.

Johnstone, refrigeration places, etc.

Stuff is pretty expensive though.

Even a basic pumpdown, replace a part, and charge will have you out:
Manifold gauge set
Vacuum pump
Recovery cylinder
Recovery machine ($$$)
Micron gauge.
Cylinder of gas

And probably a 609 cert to buy some of that stuff.

[Bogie]

Just because a vehicle comes with a part that has a particular thread doesn't mean it has to stay that way...
 
Like, the other day I was working on the shop's compressed air system... And I needed something. I could have driven the 45 minute round trip to the closest place that might have what I needed, or I could chunk some scrap into the lathe... 15 minutes later, I had the piece I needed.

[Jim147]

I'll second what Nick said about doing a little editing.

You should try finding tools to do the GM version of the Zexel compressor. I made a couple of tools for that job.

You've also learned why we use nitrogen before dumping a charge in the system.

On the van with oil spray coming out. Check to see if there is a little nut/fitting looking thing on the compressor right there. It is a pressure relief valve. One time blow. If that is what happened, you can get the one off the van you found the hose on. Then make sure you watch for overcharging or slugging the compressor with liquid.

jim

[Declaration Day]

There is always this option 

http://www.engadget.com/2007/08/11/grad-student-bolts-air-conditioner-onto-car-to-beat-texas-heat/

[White Horseradish]

Might want to edit that out...

http://www.epa.gov/ozone/title6/608/faq.html#q2

I will take you up on that, even though it's probably cached somewhere already. Wouldn't the junkyard  be on the hook for that anyway?

My AC fix. My POS truck had no charge when  I bought it. Rotate vent window so it blows on me, drive fast. 5 years now, system works perfectly. 

That is what I have done for years. Trouble is, I run into traffic on the way home from work and heat makes me sleepy. I have snoozed in traffic once and lightly rearended some guy. I don't want to do that again.

The AC on my Tahoe used to work but conked out this spring. I went to add a can to it, and when I loosened the plastic cap on the high side (it was an accident, I know you have to add the refrigerant to the low side) it hissed at me. This tells me that the fitting is bad, correct, because I presume the plastic cap is just a dust cap, and is not supposed to be holding any pressure, right?

My MIL's Volvo does that. As I understand it, there is a Schrader valve in there, like on the tires, but bigger. There  is a Schrader valve wrench for that, just like for the tire stems.

Where do you get tools for working on AC? I understand that you need a vacuum pump, and gages.

I got gauges from Harbor Fright and the pump from eBay. They would likely not stand up to daily use in a professional setting, but I am not going into business, just fixing my own stuff. Compressor tools I got from Autozone and O'Reilly. I will return them. I'm sure I can get the same quality Chinese stuff from ebay cheaper.

Just because a vehicle comes with a part that has a particular thread doesn't mean it has to stay that way...
 
Like, the other day I was working on the shop's compressed air system... And I needed something. I could have driven the 45 minute round trip to the closest place that might have what I needed, or I could chunk some scrap into the lathe... 15 minutes later, I had the piece I needed.

Don't rub it in. If I had a machine shop...

You should try finding tools to do the GM version of the Zexel compressor. I made a couple of tools for that job.

I can only imagine.. I picked up a couple of plumbing fittings of the correct size to make assembly easier.

You've also learned why we use nitrogen before dumping a charge in the system.

Yeah, if I had a supply of nitrogen it would probably be a much cheaper way to blow the compressor...

On the van with oil spray coming out. Check to see if there is a little nut/fitting looking thing on the compressor right there. It is a pressure relief valve. One time blow. If that is what happened, you can get the one off the van you found the hose on. Then make sure you watch for overcharging or slugging the compressor with liquid.

jim

I will try, but given where this thing is mounted I'm not sure I can see anything without removing it. Is there a way to tell how much oil stayed in? Or should I just assume it all blew out?

[Nick1911]

I will take you up on that, even though it's probably cached somewhere already. Wouldn't the junkyard  be on the hook for that anyway?

Maybe, but probably not.  I'm a little shaky on this, (paging 280plus and Jim147) so don't take it for gospel, but I recall that the EPA's stance is that it is up to the final disposer to recover refrigerant.  Since the junkyard is not the final disposal site of the cars (IE: after being stripped, they are usually sent to be crushed), I think they are in the clear.

Regardless!  Any person that vents refrigerant into the air has committed a crime!  It's all in sec 608 & 609 of the CAA.

[White Horseradish]

Maybe, but probably not.  I'm a little shaky on this, (paging 280plus and Jim147) so don't take it for gospel, but I recall that the EPA's stance is that it is up to the final disposer to recover refrigerant.  Since the junkyard is not the final disposal site of the cars (IE: after being stripped, they are usually sent to be crushed), I think they are in the clear.

Regardless!  Any person that vents refrigerant into the air has committed a crime!  It's all in sec 608 & 609 of the CAA.

This puts many people in a pickle. Junkyards do not have power to operate recovery equipment and usually forbid power tools of any kind.

[Jim147]

You got it right as far as I understand it. If the juckyard wanted to send the car to the shredder they have to recover. If someone else opens the system it is on that person.

If you just have a spray and not a puddle of oil, I would say add one of those two ounce cans of oil. If you have a puddle I would add about four ounces.

It is all a guess without blowing the whole system out and starting over.

jim

[Hawkmoon]

So, I embarked on the fascinating journey of swapping compressor clutch magnets. The clutch design of Harrison compressors makes me want to administer canings to the engineers. Freaking everything is a press-fit requiring lots of messing with pullers and pushers. I suppose it makes sense for ease of mass production, but repairing it is very annoying. I have discovered a few things. One, is that no one auto parts store has a complete set of tools to replace an AC clutch. I had to get three tools at Autozone and one at O'Reilly.  Two, a lot the the so-called AC tools do not fit Harrison clutches used in Chevy pickups, no matter what the box says. Three, no one knows how to work on this stuff. People are just plain afraid. Four, the tools are mostly for pulling things apart. Putting things together requires creativity. I bet auto AC shops don't even screw with this and just send them out to rebuilders.

You silly person.

Nothing in/on a modern automobile is designed, manufactured, or intended to be repaired. Everything is set up for R&R -- Remove and Replace. I'm a senior citizen and was always a car nut. I bought the factory service manual for every new car I ever had, as far back as 1966. In the old manuals, they explained (and showed) how to test components and how to replace parts like the diodes in an alternator. The shop manuals today are four times as thick, but they don't tell you how to repair anything. All they show is how to take it off and put on a new one.

[230RN]

You should have seen the shop manual for working on my old Audi Climate Control system.

First, you need to keep the car in some place where the air is 68°F for 24 hours before taking any measurements or doing any adjusting.

Unglaublich.

[White Horseradish]

You silly person.

Nothing in/on a modern automobile is designed, manufactured, or intended to be repaired. Everything is set up for R&R -- Remove and Replace. I'm a senior citizen and was always a car nut. I bought the factory service manual for every new car I ever had, as far back as 1966. In the old manuals, they explained (and showed) how to test components and how to replace parts like the diodes in an alternator. The shop manuals today are four times as thick, but they don't tell you how to repair anything. All they show is how to take it off and put on a new one.

Well, the truck isn't THAT modern. It's a 93.

BTW, the 95 van's manual actually has a section on rebuilding the AC compressor.

[Grebnaws]

The previous owner of your vehicle is always lying. That is the only correct assumption to make before purchasing a vehicle. Negotiate accordingly.

A friend of mine purchased an extremely well kept low mileage early 80's Ford F-150 and restored the A/C system on his own. It was a huge hassle and an enormous expense but he wanted it done right. Now he has a decades old carbureted v8 truck with 130hp at 9mpg and working A/C. The same investment could purchase a 10-15 year newer truck with working A/C. It gets plenty hot in central IL but I could never justify spending an entire paycheck on A/C repair, especially when the likelihood of 30 year old parts failing is high and it won't really preserve the resale value.

If I want air conditioning I have to drive the g/f's Versa. The one with a hello kitty seat belts.

[White Horseradish]

The same investment could purchase a 10-15 year newer truck with working A/C. It gets plenty hot in central IL but I could never justify spending an entire paycheck on A/C repair, especially when the likelihood of 30 year old parts failing is high and it won't really preserve the resale value.

The truck cost me $1000. I overpaid because of the stepside bed. I put in a $40 starter and rear brakes for $120 or so, but those are wear items. The AC I'm into for less than $150 so far, plus the $30 in refrigerant. I will return the compressor tools and get my money back. $1200 would not buy me a 2003 anything, especially not a 2003 truck of any kind. Also, with a 93 Chevy I am not particularly concerned about resale.

[Nick1911]

The truck cost me $1000. I overpaid because of the stepside bed. I put in a $40 starter and rear brakes for $120 or so, but those are wear items. The AC I'm into for less than $150 so far, plus the $30 in refrigerant. I will return the compressor tools and get my money back. $1200 would not buy me a 2003 anything, especially not a 2003 truck of any kind. Also, with a 93 Chevy I am not particularly concerned about resale.

It's economical because you do the work yourself.  As a general rule, products are inexpensive, labor is expensive.  Anything one can do themselves will save lots of money.

It's easy to spend $1200-$1800 on A/C repair... if you have a shop do it.