68 charger factory a/c txv

[Tripplehemi]

Does anyone have a picture of where the capilary tubes from the thermal expansion valve go on a 68 charger with factory a/c? I cant find clear info in the manual.

 

[DAMatt]

Here you go. Tried to have it seen as best as possible, but still it's all like a ball of yarn...

SO the tube that comes from the diaphragm thingy toward the front, that one is capped off, and tucked away (the one I was trying to hold in my hand). The other tube that comes off the side of the valve is connected to the A/C metal line.

Just finished converting to R134, it works perfect, but I guess for safety I have to add the electric A/C thermo switch to cycle the rv2.

 

[Tripplehemi]

thank you. That answered my question.

 

[RJRENTON]

Here you go. Tried to have it seen as best as possible, but still it's all like a ball of yarn...

SO the tube that comes from the diaphragm thingy toward the front, that one is capped off, and tucked away (the one I was trying to hold in my hand). The other tube that comes off the side of the valve is connected to the A/C metal line.

Just finished converting to R134, it works perfect, but I guess for safety I have to add the electric A/C thermo switch to cycle the rv2.

View attachment 1488714

View attachment 1488715

View attachment 1488716

The tubing coming from the diaphragm control part of the TXV, senses the EXITING REFRIGERANT TEMPERATURE and the other connection senses the REFRIGERANT PRESSURE and between the two sensed conditions, provides a balanced refrigerant flow for optimum cooling performance. The temperature sensing probe should be insulated where it touches the refrigerant tubing so its not influenced ambient temperature.
BOB RENTON

 

[DAMatt]

Bob, so what you are saying is that both tubes must be touching the same section of the metal pipe?

 

[Demonic]

I can answer here. Yes, it should be somewhere along the suction line, and insulated as Bob stated, unless the mfg instructions state otherwise. I notice the end is tightly coiled, which sometimes means that the mfg wants it in the discharge air stream. I would reach out to whomever made the kit for details.

 

[DAMatt]

I wanted to have only factory stuff, so the expansion valve was "factory replacement". Only deviation from factory right now is the r134 instead of r12, and compatible seals/hoses/oil.

I must admit I am at a loss - can anybody give me a definitive answer on where does the coiled tube go?

 

[Demonic]

Factory, there’s a sleeve in the suction line for the original TXV compensating capillary tube. I‘ll try to get a pic tonight.

Where did the valve come from/supplier? They’re the ones to ask.

 

[RJRENTON]

Bob, so what you are saying is that both tubes must be touching the same section of the metal pipe?

No...one sensor looks at temperature (touched or is in contact with the suction line insulated connection) the other connection senses pressure and must be connected to the suction line's pressure, to see the suction pressure....two independent connections. Performing different functions....
BOBRENTON
...

 

[DAMatt]

Factory, there’s a sleeve in the suction line for the original TXV compensating capillary tube. I‘ll try to get a pic tonight.

Where did the valve come from/supplier? They’re the ones to ask.

I think it was classicindustries...

 

[Some Car Guy]

I wanted to have only factory stuff, so the expansion valve was "factory replacement". Only deviation from factory right now is the r134 instead of r12, and compatible seals/hoses/oil.

I must admit I am at a loss - can anybody give me a definitive answer on where does the coiled tube go?

I have the same setup as you as far as factoryish parts and 134. I picked up a Four Seasons brand valve from Rock Auto. So far things have gone well. Did about 300 miles over the weekend and had the ac on for most of it.

the fan seems lacking on max cool, and it might’ve frozen on me at one point. Turning ac off for a few minutes got it blowing good again. I found regular ac worked best and I thought the fan did well on high with that. It’s like the outside air forced enough volume for me. I’ll probably add a relay to boost things up as Wild R/T laid out the deal very well. Having it on reg ac for hours never resulted in the slowed fan so I think it did freeze on max.

 

[Some Car Guy]

I forgot to add my capillary tube is plugged in the little rubber place on the line. Looks like two tubes are on the valve in the pic.

 

[Sixpactogo]

I wanted to have only factory stuff, so the expansion valve was "factory replacement". Only deviation from factory right now is the r134 instead of r12, and compatible seals/hoses/oil.

I must admit I am at a loss - can anybody give me a definitive answer on where does the coiled tube go?

If you have not yet figured out where that copper coiled probe goes, it fits into the well that is built into the tubing. I think it is about 4 or 5 " deep. The probe has a temp sensor on it and goes into that well that is sealed from the larger tube. Here is a pic of the well opening on my 68 that the temp probe slides into. There should be a small rubber boot that slides over the end to keep dust and debris out. I didn't have the boot so I just used a dab of air seal on mine. After looking at yours, I think you have the wrong expansion valve. It should have a small probe on the end in stead of that coil yours has. I think I have an extra expansion valve. I will try and find it for a picture.

 

[Sixpactogo]

OK.....I just checked and found the one you have. It is for a dealer installed AC. You need this one for a factory AC with the small temp probe.

Nos Mopar Air Conditioning Expansion Valve Dodge Chrysler 2936469 B E Body Plym | eBay.

 

[DAMatt]

Thanks for the wealth of info! Right now the system really works as is, even without the thermostatic electric switch for the compressor, and the wrong valve. Could it be that the wrong expansion valve is meant not to have the coiled part of the tube inside the factory jacket, but is meant to be just sticking out in the air?

How long does it take for the condenser to freeze? Since I got it working, most I have driven was an hour with no ill effects.

I would rather not replace the valve now, as I need A/C, and I am just about to decide that I am going across Europe to the Mopar Nationals on Aug 4-6.

 

[RJRENTON]

Thanks for the wealth of info! Right now the system really works as is, even without the thermostatic electric switch for the compressor, and the wrong valve. Could it be that the wrong expansion valve is meant not to have the coiled part of the tube inside the factory jacket, but is meant to be just sticking out in the air?

How long does it take for the condenser to freeze? Since I got it working, most I have driven was an hour with no ill effects.

I would rather not replace the valve now, as I need A/C, and I am just about to decide that I am going across Europe to the Mopar Nationals on Aug 4-6.

The TXV sensing element MUST be in contact with the evaporator's outline to be able to "know" the refrigerant outlet temperature to control the liquid refrigerant entering the Evaporator. Too much liquid refrigerant entering the Evaporator will cause the condensed water, on the air side of the Evaporator, to freeze, blocking air flow to the passenger compartment.
Your second statment......the condenser will never freeze......it's the EVAPORATOR that will freeze for reasons noted above. After your journey, consider installing the correct TXV properly.....then you not need to be concerned about evaporator freezing. Just my opinion of course....
BOB RENTON

 

[DAMatt]

I am by no means an expert on A/C, as seen by my mixup above. What would be the best course of action using the expansion valve that I already have? Put as much as it fits of the coiled tube inside the factory space on the hard line? Coil it around the pipe and insulate? Leave it as is? Something else?

Funny thing, after an hour of A/C, i have a small puddle on my valley pan. Is it normal?

 

[RJRENTON]

I am by no means an expert on A/C, as seen by my mixup above. What would be the best course of action using the expansion valve that I already have? line? Coil it around the pipe and insulate? Leave it as is? Something else?

Funny thing, after an hour of A/C, i have a small puddle on my valley pan. Is it normal?

YES.....

Put as much as it fits of the coiled tube inside the factory space on the hard

The sensing bulb controls the TXV and the liquid refrigerant entering the Evaporator. It must be insulated against underhood ambient temperature.....it can get to 120°F ...... UNLESS insulated, the TXV will be wide open, flooding the Evaporator with refrigerant.
BE VERY CAREFUL not to kink or damage the TXV capillary tubing or the TXV will not operate correctly resulting in no cooling. The capillary tubing contains a gas under pressure to operate TXV.
Your accumulated water on the valley pan is condensation.
BOB RENTON

 

[DAMatt]

Is this a better solution till I get the proper valve? It would be wrapped in tape or something to further insulate

 

[RJRENTON]

Is this a better solution till I get the proper valve? It would be wrapped in tape or something to further insulate

View attachment 1499563

YES......The capillary tube, shown wrapped around the refrigerant line, specifically, just the end of the tubing, must be insulated to accurately measure the TEMPERATURE of the exiting gas. The other connection shown by the brass hex nut, should also be connected to the TXV, to provide the TXV a PRESSURE balanced connection to provide TEMPERATURE AND PRESSURE control of the TXV for accurate refrigerant metering to the evaporator.
BOB RENTON