Tired of Fixing this Ford AC

[deltap10]

Many times automotive system ac failure is called the black death. Lots of black crud contaminating the system. If not flushed clean another failure happens soon. Parts houses usually will not warranty the new comp. without a new accumulator/ drier. Thorough leak test is a must - usually means owning an electronic sniffer. Check air side of evap. for debris like leaves etc. I once found a plastic shopping bag had sucked into system. Micron gage is only way to verify system is dry. Charging 134A must be done as a liquid. Check if tank needs to be inverted. Charge most of weight into high side with system off. Start system and finish charge slowly into low side. Comp. clutch will remain engaged when charge is nearly complete. Stop charging when scale reaches nameplate amount. With cooling on max. a thermometer placed in dash vent should read mid to high forties. Good Luck

[bja105]

Timebuilder, when were those Voyager failures, which production years? I just bought a 2000 Caravan with a leak I have not looked for, yet.

[disston]

I looked closely at the evap when I did the heater core. It was not doable with out extra disco. So it didn't get done at that time. I realize some of the work is the same. But not all.

I understand it's faster, liquid. So with compressor unplugged so it doesn't start and the tank upside down on the scale, the scale is on the ground. The system is vacuumed with one hose and the pump is isolated with it's own valve. Low side valve is closed and liquid is put in high side. When scale reads correct amount of gas is installed the tank is turned off. How does the system get all of the liquid and gas out of the hoses? Isn't some of the gas left in the hoses? Or after tank is turned off and the system is started the low side can be opened to suck in the rest of gas?

I hope this is not too much of a DIY question. What am I not getting?

I have to turn in soon. I'm quitting cigarettes tomorrow. I hope.

[disston]

OK. That helps a bit about the liquid mystery. I'll be able to handle liquid I think.

I am replacing the condenser, new. The compressor, new. The accumulator/dryer, new. The hoses were flushed with Kwik Klean. The evap was flushed with the same. I used two quarts of flush. The hoses are in good condition. I got a lot of black debris out of stuff, especially the evaporator. All of this was done a week ago.

I'm going to take the system apart again to put in the stock orifice tube.

I'm going to check into getting some nitrogen but I may have to take my chances. I know this doesn't sound professional, I can't help it. I'm a little over whelmed at the moment. I'll see if I can get some nitrogen.

This is the fourth time I have tried to fix this system. I've gotten black stuff out of it every time. I know about black death. I never flushed the system before. I'm sure that helps. Might be the key I think. I bough a 4 cfm Robinair pump. In the past I've only had access to an antique pump that belongs to my housemate. The Robinair 15424 seems very strong but I don't have a Micron gauge. I figure 2 hours of pumping have got to be enough. And I would let it sit over night but I've been reading a lot on these pages and this now seems like a bad idea because the hoses will leak?

[cy]

fixing it 4 times ... you might want to take it by a pro for another opinion if nothing else. sure sounds like you've replaced a lot of parts not necessary.

what the nitrogen does is to pressurized system to flush out leaks that will not show up until operating pressures are reached. a small shot of refrigerant is sometimes used to allow use of a sniffer.

a micron gauge is the only way to get an accurate vacuum reading. how deep/long vacuum can be held is another indicator of a tight system. sticking a vacuum pump for two hours on a system that leaks will net you zero.

working on AC is extremely equipment intensive as you are finding out
that's why taking it to a pro ... sometime is the cheapest solution.
buying all the tools and learning how things work is my preferred way

so don't give up ... if you want to learn how AC works

[timebuilder]

Timebuilder, when were those Voyager failures, which production years? I just bought a 2000 Caravan with a leak I have not looked for, yet.

I believe they were in the mid 90's.

Find the rubber condensate drain and with thew system dry, stick your leak detector in there. If your evap is the problem, it will go nuts. If you still have some charge in the system, that is. If not, give it a few Oz's and pressurize with N.

[timebuilder]

OK. That helps a bit about the liquid mystery. I'll be able to handle liquid I think.

I am replacing the condenser, new. The compressor, new. The accumulator/dryer, new. The hoses were flushed with Kwik Klean. The evap was flushed with the same. I used two quarts of flush. The hoses are in good condition. I got a lot of black debris out of stuff, especially the evaporator. All of this was done a week ago.

I'm going to take the system apart again to put in the stock orifice tube.

I'm going to check into getting some nitrogen but I may have to take my chances. I know this doesn't sound professional, I can't help it. I'm a little over whelmed at the moment. I'll see if I can get some nitrogen.

This is the fourth time I have tried to fix this system. I've gotten black stuff out of it every time. I know about black death. I never flushed the system before. I'm sure that helps. Might be the key I think. I bough a 4 cfm Robinair pump. In the past I've only had access to an antique pump that belongs to my housemate. The Robinair 15424 seems very strong but I don't have a Micron gauge. I figure 2 hours of pumping have got to be enough. And I would let it sit over night but I've been reading a lot on these pages and this now seems like a bad idea because the hoses will leak?

Don't feel too bad.

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.

[disston]

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.

[disston]

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.

[disston]

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.

[ZeroTolerance]

Big Blue is the sheet!

[disston]

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?

[ZeroTolerance]

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

[Gunslinger]

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.

[disston]

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.

[VTP99]

[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.

[disston]

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.

[madhat]

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.

[disston]

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.

[mcr]

Don't overfill the oil! If the system calls for 8 oz. total, don't just add the 8 in. The evap usually counts for 1 oz., The accumulator 1 oz. and the condenser 1 or 2. If you add to much you can destroy the compressor. The compressor does not want to pump liquid. Measure any oil that comes out of the old compressor. I farmed out an evap changeout at a shop and the dummy put the full oil charge into the evap. The compressor was clanging and banging like a Model A