How to fix A/C System?

[BonesDT]

2.5 years ago, my Ex's fan belt busted and took a hole in an A/C line with it and all the coolant leaked out.

Now I want to fix it. I have a new A/C line that I've been storing with the caps on it. I'm thinking that I need to get a new drier (black canister) since it probably over-absorbed external moisture.

Do I need to do anything else? Do I just put on a new drier and the hose, then fill it up with R-134a to pressure?

I'm worried I've been driving around with a hole in the A/C system for 2.5 years and dirt has traveled past just the hose section. Should I do a flush of some sorts?

While we're at it, my '89 Dakota needs new coolant, but it's got the old R-12 system. Can I convert to the new 134 simply by using the port adapters or do I need to replace everything (compressor, drier, evaporator, hosing, etc.)?

 

[96eb96]

2.5 years ago, my Ex's fan belt busted and took a hole in an A/C line with it and all the coolant leaked out.

Now I want to fix it. I have a new A/C line that I've been storing with the caps on it. I'm thinking that I need to get a new drier (black canister) since it probably over-absorbed external moisture.

Do I need to do anything else? Do I just put on a new drier and the hose, then fill it up with R-134a to pressure?

I'm worried I've been driving around with a hole in the A/C system for 2.5 years and dirt has traveled past just the hose section. Should I do a flush of some sorts?

While we're at it, my '89 Dakota needs new coolant, but it's got the old R-12 system. Can I convert to the new 134 simply by using the port adapters or do I need to replace everything (compressor, drier, evaporator, hosing, etc.)?

No FLUSH! Be sure to wear googgles around A/C.
Definately replace the drier.
It is doubtful dirt got in, but mosture sure did.
You need a vac pump to suck all the moisture out of the system.
You can't beat the price here:http://www.ctd4ac.com/vacpumps.html. It cost less than what a shop will charge for the service.

Did the hose break when the A/C was running? You may have to add some oil too. Figure around 3oz.

Also, (optional) I would take out the compressor, put oil in it and spin it a few times, and leave it clutch face down for a while(30 min). Then drain the dirty oil. Why? Because if it wasn't working for 2.5 years the shaft seal is dry as a bone and may get ruined before the pressurized oil hits it. Also it cleans the crap out of the compressor, maybe prolonging its life. I was told to do this by a pro. Measure the oil that is already in the compressor (let it leak out) and put a bit more back in when you reinstall. It may be dry, add an ounce then. Replace any O-rings you disturb. Coat them well with oil or something called NYLOG BLUE.

You may also want to replace the orifice tube, its a few dollars. It looks like a long straw with a wire mesh and it inserts into the bottom evaporator tube. You remove it with needlenose pliers. This device acts as a filter and pressure device for the A/C system.

For the dakota, I would goto www.ackits.com and ask on their forums. They are pros who volunteer their time and can give you the best answer to that question. Generally you just replace the dryer, replace the ports, and vac down the system. They are also great people to deal with, they have a big operation in arizona where they fix auto A/C, so its not a flybynight web front. (not advertising, but they helped me a lot)

 

[BonesDT]

Why no flush? I hope you were referring to the $45 vacuum.

It broke on a Christmas Eve, so it wasn't running.

That ackits.com is a great site. It's great to know that when I have $650 lying around, I can buy an entire brand new R-134a system specifically for my Dak!

This is what I don't get. If I buy a replacement A/C part for an 89 (which was originally made for R-12), can I assume that it is R-134a compatible since it is being sold today? It wouldn't make sense to manufacture a replacement part that is only compatible with R-12 considering you would have to recharge the entire system after making the replacement.

 

[BonesDT]

What's the difference between Nylog Blue and Red?

 

[BonesDT]

Ok, here's my plan, please tell me if I'm on the right track:
1) manually "flush" compressor with PAG-46 oil ($7.70) keeping track of the amt of oil that goes in and out.
2) add ~2oz oil to new accumulator/drier ($23.24) and oil to compressor. Entire system should have 7 oz oil in it.
3) Should I flush the evaporator and condensor? How can I tell how much oil is in them?
4) inspect and clean outside of evaporator with some household cleaners to prevent odor
5) replace broken hose, accumulator/drier, orifice tube ($0.86), and any o-rings I run into ($8.34) lubricated with Nylog Blue ($6.90).
6) evacuate system with 1.5 CFM vacuum ($99.50). What's the difference between 1-stage and 2-stage?
7) Recharge system. Do I need a 2-gauge-3-hose manifold, or can I make due with something less. This would be another ~$100.

 

[96eb96]

Ok, here's my plan, please tell me if I'm on the right track:
1) manually "flush" compressor with PAG-46 oil ($7.70) keeping track of the amt of oil that goes in and out.
2) add ~2oz oil to new accumulator/drier ($23.24) and oil to compressor. Entire system should have 7 oz oil in it.
3) Should I flush the evaporator and condensor? How can I tell how much oil is in them?
4) inspect and clean outside of evaporator with some household cleaners to prevent odor
5) replace broken hose, accumulator/drier, orifice tube ($0.86), and any o-rings I run into ($8.34) lubricated with Nylog Blue ($6.90).
6) evacuate system with 1.5 CFM vacuum ($99.50). What's the difference between 1-stage and 2-stage?
7) Recharge system. Do I need a 2-gauge-3-hose manifold, or can I make due with something less. This would be another ~$100.

List Looks good.

Get the manifold here:

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=92649

They cost a bit less in the store if there is one around you. We have one in Albany.

They also have a 1.2 CFM version of the pump at harbor freight for $69 bucks, but the link I gave you will give you great support on the pump. They are a local company in Newburgh, NY.

The cheaper compressor pumps aren't the greatest since they don't have the capacity to pull a strong vacuum. Also, they will overwork the compressor. I strongly suggest not getting that. If you are on a budget get the one from HF.
http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=98074
http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=98076

You should pull vac for a good 2-3 hours.

Flushing is not necessary unless you have an exploded compressor. You will often leave flush residue in the system. Also, flushing a condenser is usually futile because of the design. If the compressor explodes it is just replaced. A/C kits would not advise a flush unless you had a catastrophic compressor failure.

If you replace the accumulator, drill holes in the old one and see how much comes out. I would add 6 oz of oil to the system in your case(taking into account the compressor). There was a TSB that its ok to add a few oz more of oil to the explorer(2 or 3 I think). I had an evaporator crack and there was barely any oil in the system. Nice oil puddle under it though. Each item you replace (hose, orifice, accum) is approx 2oz according to the manual.

NYLOG blue is for R134a systems, and is superior to using oil. Make sure to use a healthy amount on both the o-rings and the area on the fitting between and beyond the outer 0 ring. This is how the outer 0 ring is kept pliable. For the orifice you can use oil, because it comes with the orings on the body. you want to dip it in the oil so it seeps under the orings.

The evaporator teardown is an optional step. If you do that REPLACE YOUR BLEND DOOR. It is definately accessible at this point. The part cost a few bucks at napa or advance. You can wiggle it out from the Evap opening. Search the site for the part number. Doing that may be worth the trouble. (not sure if its a problem for 99s though), maybe someone else can chime in.

If you want to know more about the pumps, call classic tool design(I posted it in the first post). He will explain everything to you.

You will also need a spring lock removal tool. If you are creative you can make one out of a motor oil bottle cap or safety seal. Just cut a strip that matches the circumference of the fitting, and slip it into the spring lock coupling, trying to displace the garter spring. Then slide the fittings apart.

The garter springs can be replaced too, you can get them at napa or from ackits.

 

[96eb96]

Why no flush? I hope you were referring to the $45 vacuum.

It broke on a Christmas Eve, so it wasn't running.

That ackits.com is a great site. It's great to know that when I have $650 lying around, I can buy an entire brand new R-134a system specifically for my Dak!

This is what I don't get. If I buy a replacement A/C part for an 89 (which was originally made for R-12), can I assume that it is R-134a compatible since it is being sold today? It wouldn't make sense to manufacture a replacement part that is only compatible with R-12 considering you would have to recharge the entire system after making the replacement.

All dryers today are R134a compatible, they use an upgraded desiccant.

 

[BonesDT]

Is there any significance to the single-stage/dual-stage vacuums? Should I get an additional vacuum gauge so I know how much I'm pulling and if there is a leak and it's loosing pull?

Great, I'm almost ready to order my parts and tools:
1) I already have my hose and the de-coupler tools

From ackits.com:
2) DEC PAG 46 oil ($7.70)
3) accumulator/drier ($23.24)
4) orifice tube ($0.86)
5) o-rings I run into ($8.34)
6) Nylog Blue ($6.90)
7) Can Tap ($10.40)

From Harbor Freight:
8) Manifold Gauges ($42.99)

9) Vacuum ($69.99-95.99)
10) Vacuum gauge?
11) I'll look into the blend door
12) 3 R-134a cans at my local store

 

[96eb96]

Is there any significance to the single-stage/dual-stage vacuums? Should I get an additional vacuum gauge so I know how much I'm pulling and if there is a leak and it's loosing pull?

Great, I'm almost ready to order my parts and tools:
1) I already have my hose and the de-coupler tools

From ackits.com:
2) DEC PAG 46 oil ($7.70)
3) accumulator/drier ($23.24)
4) orifice tube ($0.86)
5) o-rings I run into ($8.34)
6) Nylog Blue ($6.90)
7) Can Tap ($10.40)

From Harbor Freight:
8) Manifold Gauges ($42.99)

9) Vacuum ($69.99-95.99)
10) Vacuum gauge?
11) I'll look into the blend door
12) 3 R-134a cans at my local store

The manifold set and the electric HF pump is all you need as a minimum. Dual stage may pull a bit stronger vac than a single stage. Classic tool pumps pull down to 50 microns, the HF ones 75 microns. Even 150 microns is acceptable in the real world. The HF pumps aren't available in store, and its listed as a new item online. I would have bought that in a heartbeat if I saw it!

If you want to get really scientific, 0 microns is an absolute perfect vacuum. The goal here is to boil moisture by lowering vapor pressure of the system. Water will easily boil at room temp if you go down to say 200 microns (about). You can buy a device to measure microns of pressure. I wouldn't personally, but its fine if you want to. Here is an example(you can probably get one with a real digital display, this one needs a DVM):

http://www.hvactestgear.com/avg2-fieldpiece-digital-vacuum-gaug.html

They have them on ebay if you search under micron gauge.

After 15 minutes of Vac, turn off the pump and watch the gauges for about 1/2 hr. If you see no movement, you have a sealed system. Of course, if you have a tiny tiny leak and lose 500 microns the gauge set will not show it(thus the micron gauge). Then again most leaks happen when you are under pressure anyway. If the gauges don't move, start the pump and pull about 3 hours of straight vac. This is the advantage over a shop, they may have a bit stronger pump but will do it for 20 minutes max. Again shut the pump and look for any needle movement. Close both knobs then the vac pump.

Connect the can to the yellow hose.Purge air when you change cans from the hoses by slightly unscrewing the fitting at the center manifold end. Let out a tiny bit of freon, then twist it back. Empty your first can into the system. Open the low side blue knob. Make sure the high side knob is closed during charging or you can explode a can!
Of course wear eye protection.

Auto part stores may have the can taps for a bit less, maybe 6 or 7. Also inspect your springlocks when you remove them, you can get that locally.

Also remember that 1lb of freon = 1 can (12 oz) not 16 oz. Check the underhood sticker.

 

[SPORTEXP]

You could buy the vacuum pump or modify that portable tire pump you got laying around for nothing. Just add a fitting on the intake port and hook it up to your gages. It wont run your battery down vacuuming out the system.

 

[BonesDT]

I'm still a little confused about the evacuation, I haven't hooked up a vacuum and tried it yet. Do you just turn the vacuum on and leave it on for an hour or more? Do the dual A/C manifold gauges tell me if I'm losing the vacuum, i.e. have a leak?

 

[moon lake rick]

a/c

The posts to this a/c subject seen to be "right on". All you people sure do your best to help one another. USA is the greatest..

 

[SPORTEXP]

Theres no rocket science to it just draw it down for about 15 minutes, close the valve, turn off the pump, wait 20-30 minutes, check the gage to see if the needle has moved, and if it hasn't open the valve to the R134 and charge (the vacuum will suck it in) the system.

 

[SPORTEXP]

thanks for the post moon lake, I'm not a pro, but I've been through this a few times.
Don

 

[96eb96]

I'm still a little confused about the evacuation, I haven't hooked up a vacuum and tried it yet. Do you just turn the vacuum on and leave it on for an hour or more? Do the dual A/C manifold gauges tell me if I'm losing the vacuum, i.e. have a leak?

The manifold knobs control airflow to the center hose. The gauges are always read the system pressure regardless of the knob position.

Hook up the vac machine to the yellow hose. Open both manifold knobs. Draw vac for 15-30 min. Shut off the manifold knobs, then the pump. Keep an eye on the gauge, if you have a leak it will slowly drop. wait about 15 min. If you don't see any gauge movement you are probably OK. The oil you bought has dye in it, so if there is a leak it will be apparent when it runs(with a blacklight).

After this, open the manifold knobs and run the pump for 2-3 hours. Moisture can be trapped deep within the system and needs time to boil out. Some will say this is overkill but its insurance that all the moisture is gone even if the pump is less than perfect. Might as well give the pump a workout!

Now you are ready to charge the system. The car should be off. Shut both knobs. Remove the pump and attach the can to the yellow hose. Open the blue knob. Slightly loosen the yellow hose at the manifold for a second. This will allow the air to escape from the lines, close the fitting. Open the blue knob, and freon will rush in. Make sure the red knob is closed when you charge. When the can is almost empty, start the truck. Eventually as the can discharges your compressor will start rapid cycling. When you think the can is empty, shut the blue knob, remove the can, tap the next can, connect it, bleed the air, open the valve , make sure the can is upright when you charge, you dont want liquid freon entering the compressor!

Safety first, make sure to wear googles!