Broken part on AC does it matter?

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johnnycuda

johnnycuda

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Broken part on AC does it matter? Hey guys I'm sure it needs to be fixed before I can get the air condition to work just wanted to doublecheck with you guys it's a little copper line by the firewall here's a picture it looks like it to $300 part
Also there's no power going to the blower I did jump the blower and it works so it has a ground just no hot from the switch! Any help will be greatly appreciated guys you are the best with these things Johnny!

IMG_2679.JPG
 
That is a F type expansion valve. The expansion valve removes pressure from the liquid refrigerant to allow expansion or change of state. So it has to be there.
Your switch, is there power to the switch? check fuse and wires. If yes and when you select fan speed and fan doent run it is the switch or the coil in the heater box that it plugs into.
 
Mikes270dart said:
That is a F type expansion valve. The expansion valve removes pressure from the liquid refrigerant to allow expansion or change of state. So it has to be there.
Your switch, is there power to the switch? check fuse and wires. If yes and when you select fan speed and fan doent run it is the switch or the coil in the heater box that it plugs into.
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Thanks
 
The little copper tube is called a capillary tube and is filled with ammonia gas and should be soldered on the end. If it is broke you might be able to send it to vintage air and they might be able to replace it. You should give them a call.
 
brian6pac said:
The little copper tube is called a capillary tube and is filled with ammonia gas and should be soldered on the end. If it is broke you might be able to send it to vintage air and they might be able to replace it. You should give them a call.
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That does not appear to me to be what is broken. There are TWO small tubes. One is filled with something (I don't know about ammonia) and is the temperature probe. The other one goes to the flare nut and is simply a pressure fitting. It appears to me the tube is broken near the flare nut. THAT could be easily fixed. (It's the equalizer) The opposite end of that tube connects to the TXV and could not be so easily fixed if at all.

OP: You need to post clarifying photos

In the diagram, the tube coming out the top of the TXV and going into the "well" is the temp probe. The tube which appears broken to me is the equalizer.......we need to see where it's broken at the TXV

equalizer.jpg
 
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If memory serves you can get rid of the txv valve altogether and use a simple expansion (orifice tube I think it is called) valve like modern cars use. I think it was the guy who owns Polar Bear AC that was telling me about it. I want to convert mine when I change the compressor over from rv style to sanden type. It is such a cleaner install and no moving parts to break.
 
ValiantOne said:
If memory serves you can get rid of the txv valve altogether and use a simple expansion (orifice tube I think it is called) valve like modern cars use. I think it was the guy who owns Polar Bear AC that was telling me about it. I want to convert mine when I change the compressor over from rv style to sanden type. It is such a cleaner install and no moving parts to break.
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A TXV is a marvelous device and should NOT be downgraded with an orifice/ cap tube unless say, you simply cannot get one to replace it.

A TXV protects the compressor, and helps the system to operate under widely various conditions.

The OEM setup you see here with the external pressure connection know as "external equalized" is that much better. TXV's in general have a very low failure rate. In my days working on AC/ refrigeration/ heat pumps I've replaced a few, and "darn few."
 
Charrlie_S said:
Just replace the valve, 1968 DODGE DART 4.5L 273cid V8 A/C Expansion Valve | RockAuto
Also replace the drier, 1968 DODGE DART 4.5L 273cid V8 A/C Receiver Drier / Accumulator | RockAuto
Evacuate and recharge.
Do not consider using an orifice tube, instead of the valve. It requires other mods to the system, and does not work as well in this type of application.
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Charlie, do you know what other mods are necessary? I don't want to step on the op's post but am very interested.

67dart273, funny you should mention it. The txv in our Lennox heat pump is about to cost us $1000 or there abouts... We are leaning toward just installing a new system.
 
ValiantOne said:
Charlie, do you know what other mods are necessary? I don't want to step on the op's post but am very interested.
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No mods are necessary to replace the TVX, and have the system work correctly.

If you mean what is necessary to convert to a orifice tube, I'm not going to go into that, here. If you don't have the knowledge of A/C systems to know about the TVX, you will just get into a can of worms. I have been working on all types of A/C and refrigeration systems, since the mid 1960's and have no idea what size tube to install, without a little trial and error. You would also have to remove the receiver/drier, add an accumulator, make some new hoses, change the compressor control, etc.
 
Great link to an affordable part. Mopar still uses expansion valves, though they are more compact today. My 80's M-B also use. GM used fixed orifices, which is inferior evaporator control.
 
Charrlie_S said:
No mods are necessary to replace the TVX, and have the system work correctly.

If you mean what is necessary to convert to a orifice tube, I'm not going to go into that, here. If you don't have the knowledge of A/C systems to know about the TVX, you will just get into a can of worms. I have been working on all types of A/C and refrigeration systems, since the mid 1960's and have no idea what size tube to install, without a little trial and error. You would also have to remove the receiver/drier, add an accumulator, make some new hoses, change the compressor control, etc.
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Thanks Charlie. The guy who I talked to a few years back made it sound as though it was a common and fairly straight forward process. If it is not, maybe I can convert it to the type of valve my 1980 Lebaron M body uses. It is all in one block against the firewall and is much cleaner under the hood.
 
ValiantOne said:
If it is not, maybe I can convert it to the type of valve my 1980 Lebaron M body uses. It is all in one block against the firewall and is much cleaner under the hood.
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I'm done. You don't seem to want to repair it correctly (and easily), and by your first post, you don't have enough basic A/C knowledge to do otherwise.
 
Charrlie_S said:
I'm done. You don't seem to want to repair it correctly (and easily), and by your first post, you don't have enough basic A/C knowledge to do otherwise.
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My system currently works fine. What I do want, when I remove my current 273 w/ rv compressor and replace it with the 360 mag, w sanden compressor I am currently building, is to get rid of the big ugly valve currently on the car and replace it with something more aestheticly pleasing to the eye. Basic resto-modding in my book. Sorry my first post was a bit scatterbrained, it has been a long time since I worked in the auto business. I was Chrysler master tech back in the early 90's. But it has been about 20 years and much has changed since then. I sincerely wanted to pick your brain, and thanked you for the info you did give. Sorry to have offended you. Perhaps we can have a laugh if I see you again at Mason Dixon for another slant race. Best.
 
OK, sorry. Actually not much has changed as far as the mechanical side of A/C, and it is not rocket science. Controls, now that is a different story. For what you want to do, the biggest problem will be adapting the inlet and outlet for the evaporator to a different metering device. The rest will be pretty straight forward. Use a new parallel flow condenser, new "o-ring" style drier, and new barrier style hoses. Use a dual pressure switch on the drier, and a thermostatic switch for compressor cycling. Charge with R-134a. Forget about any of the oddball refrigerants. R-12 is too hard to get, and pricey, R1234, needs special equipment, and is VERY pricey. Any other will void compressor warrenty.
 
Charrlie_S said:
OK, sorry. Actually not much has changed as far as the mechanical side of A/C, and it is not rocket science. Controls, now that is a different story. For what you want to do, the biggest problem will be adapting the inlet and outlet for the evaporator to a different metering device. The rest will be pretty straight forward. Use a new parallel flow condenser, new "o-ring" style drier, and new barrier style hoses. Use a dual pressure switch on the drier, and a thermostatic switch for compressor cycling. Charge with R-134a. Forget about any of the oddball refrigerants. R-12 is too hard to get, and pricey, R1234, needs special equipment, and is VERY pricey. Any other will void compressor warrenty.
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Good info. Thank you. I know we have stepped all over the op's post here (sorry op!) so I will start a new thread when the time comes. The good news is I am already running 134, I installed a parallel flow condenser when I rebuilt the system back in 2008. Too bad the custom lines I had crimped up will be useless with the new compressor/system config. I can see where adapting the evap will be difficult. The rest of it I'll have to learn. Will you be at Mason Dixon for the fall slant race? Maybe I can pick your brain in more detail. Thans again.
 
ValiantOne, We had a problem, in this thread. I wasn't looking at who was posting and thought you were the OP. My apoliges to both.
I won't be at M-D. Probably will not be doing any more traveling. My Toyota truck finally had to be retired (18mpg towing), and my Dodge only got 8.3 on the trip to Wilkesborro.
 
I expect the expansion valves used on modern Mopars would work fine. They are much more compact than the 1970's OE design. I don't know how to plumb them in cleanly in a resto-mod, but perhaps somebody makes something. Most AC kits use a custom cabin box, some being knee-knockers and some all behind-dash, but I think both styles have an integral expansion valve. Indeed, in old knee-knockers it looks very similar to the 1970's Mopar under-hood valve. For those, you just need a firewall feed-thru, of which there are many choices. Some have O-ring stubs for both AC and heater tubes, in a compact package.
 
BillGrissom said:
I expect the expansion valves used on modern Mopars would work fine. They are much more compact than the 1970's OE design. I don't know how to plumb them in cleanly in a resto-mod, but perhaps somebody makes something. Most AC kits use a custom cabin box, some being knee-knockers and some all behind-dash, but I think both styles have an integral expansion valve. Indeed, in old knee-knockers it looks very similar to the 1970's Mopar under-hood valve. For those, you just need a firewall feed-thru, of which there are many choices. Some have O-ring stubs for both AC and heater tubes, in a compact package.
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When I ever get around to it, if I find a compact, semi simple solution I'll start a thread on it. First, finish building my new engine! Thanks all
 
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