Don't feel too bad.
Originally Posted by disston
One very large chain uses (as of 2000) shop air instead of nitrogen to pressurize the system. No kidding.
Also, it is a common practice to observe the low side needle at 29.9" hg and let is sit there with the pump running for 30 mins. No micron gauge. I'll bet only one out of 5000 auto ac shops even owns a micron gauge.
Two hours and put the charge in. Obviously, you enjoy learning, and in some ways, you are already equaling what you would be paying for, as AC is not a "specialty" in the auto world.
When your charge is in and the system is running, you can spray a soapy solution on those hoses and connections, and bubbles in the sprayed areas will show you all leaks except for the evap, so that's a "process of elimination" for that component.
[Avatar photo from a Florida training accident. Everyone walked away.]
2 Tim 3:16-17
RSES CMS, HVAC Electrical Specialist
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I have used soapy water for years chasing leaks in the old restaurant I worked at years ago. I bought a bottle of some kind of soapy water, I think it's called Big Blue, just to get a squirt bottle to do this, he he, I'll be able to make my own when Big Blue runs out.
I do think that is strange about testing with compressed air but have no doubt that these things get done.
I also realize that Auto AC work is usually done by somebody that also does everything else. Some are better than others and some have a bit more equipment or know how to use it. The people I work around are not the sharpest knives in the tool drawer. But the ones that can survive are pretty cool guys and I know some smart people too.
I do good work but only have to do one car and one motorcycle. I think I should take up a bit more AC work but as another contributor said it's very, very hard to make a buck. My problem also seems to be just getting along with those people called "customers". I have never subscribed to the rule the customer is always right. Just doesn't work for me. If I'm the one who has to be responsible then I'll tell them what you are going to get.
I don't have a leak detector right now. I used to have one of those that burned propane years ago. My boss, Bobby, got pretty good at using it. I think he still has it because I left it behind when I left there. Will consider a leak detector some day. But I think you already know this. That is good info for me about the small charge and then nitrogen.
Another long message lost because I don't use the system right or I think I'm signed in when I'm not.
I've owned the car 6 years, I think. It was a wreck when I got it but I didn't know that. Have had many wiring problems. First was part of the blower motor circuit that shorted and blew the big fuse when ever I went over a large bump.
I am driven to fix my own stuff. It's not a matter of saving a couple of bucks.
Now have flushing kit. Used two quarts of Kwik Klean. Putting stock orifice tube back. Going to pump and fill.
Wish I could afford a micron gauge, maybe next year. Nitrogen? I'm working on it.
The only other mechanic my cars ever see is the guy in some wrecking yard who picks it up with one of those giant claws while I remove the tires and he drops it in a crusher. Oh yes, I get somebody to do a front end alignment once in a while. That one is cost effective.
I don't know what you mean, Zero. I think it's some kind of one of those "Blue" jokes? It was also some brand name of soapy water I ordered when I was getting some other stuff some where. I got it to have the spray bottle. I didn't have one. But you actually do like this brand?
About leak detectors: I would think nobody uses those ones that burn propane anymore? But I don't know. I was not good with the one I had years ago.
So it's electronic or infared dye? The two best choices? or there is something I'm missing. I think the pros might have the electronic but install the dye sometimes also?
I mean it is great stuff lol. Don't use dye. The big blue should suffice for all the connections and hoses/pipes in the engine compartment. The D-Tek Select is one of the better leak detectors in my opinion and many others, but costs around $350
First, throw that variable orfice tube away and use the OEM. Second, you need to leak test the evap with an electronic sniffer. The Tek-mate is great for this. They are presently on ebay for 150 bucks new. the vacuum must be done for a few hours or more. Believe me, I used a micron guage and it takes that long on automotive work. Just about every automotive repair shop does not use a micron guage and only pulls a vacuum for 30 minutes to an hour due to their flat rate systems. If it is your own vehicle, do an over night evacuation. The oil for R134 absorbs moisture faster than you think.
Thanks. I think I knew the variable orifice tube was not a good idea even before I bought it. Nobody seems to like it. I will take it out. I'll be able to vacuum for a couple of hours but don't want to leave stuff outside overnight.
[QUOTE=deltap10;10129642]Charging 134A must be done as a liquid. Check if tank needs to be inverted.
134a is a single component refrigerant. It can be charged liquid or vapor. But as noted liquid is the fastest way to get it in the system.
Thanks . I'll put in liquid on the high side. If I can't get it all in I'll put more gas in the low side after starting system. Will put in only the amount on sticker under the hood. Have a scale. Car broke down today, fuel pump, so didn't get to put in R134a.
I have a list of stuff to do before I do this. I'll make a report here.
Wanted to say thanks tho for all the help.
When I replace a Vehicle compressor, I take the old compressor and dump the oil into a measuring cup. I put that oil in my recycle countainer. I take the new compressor and do the same. Then I put the same amount of oil that came out of the old compressor, back in the new compressor. If you didn't do this the first time, you'll have to flush the system. Ford makes a liquid line filter dryer for service, also I've replaced the orifice with their kit. Go to FordPartsonline, to get your parts, I use The Ford dealer in Las Vegas. A worn Idler pulley can screw up your compressor too, especially if it's next to your compressor. Ilike to paint High Vacuum Sealant on all the "O" ring fittings, keeps the dirt out of the retention springs and "O" rings.
I only have to make it work till I retire.
Thanks madhat. I do use a lot of dealer, Ford parts for my car. I bought an after market compressor tho, no excuse really, just that I don't always buy Ford parts for my car. The compressor I have came with some special oil additive that the lititure warns not to remove so I've left it in place. I've added 8 additional oz's of PAG 46 or is it 48. The system calls for 7 oz. I still have to take the fancy orifice tube out and put in the stock one. Will do that the next warm day, over 70, and vacuum fill the system.
I replaced the condenser, new. Replaced the compressor, new. And replaced the accumulator/dryer, new. The rest of the sytem has been flushed well.
I have a Robinair 4 cfm, 15424, vacuum pump. A 30 tank of R134a and a digital scale, Mastercool, I think. I have a new set of Robinair R134a gauges.
I'm confident the system is cleaner now than it has ever been since I bought the car 6 years ago.
I do have an inline filter for the liquid line. I've not put that on. It's a universal, probably made by 4 Season's. Do you think these are a good idea? It's not too late to put it on. I haven't filled the system yet.