A/C rebuild

[josehf34]

My '74 fury is a factory A/C car but it has never worked since I own the car. I can't try if it works because each time I turn on the fan the fuse blows (so I don't have heater or A/C)

I read this old systems uses R12 coolant which isn't longer used because it damage the ozone layer, so I've to upgrade the system to use R134a coolant.

I read the stock A/C compressor is very inefficient, it weights too much (45lb) and draw too much power (up to 20hp). Most of the articles I read recommends to upgrade the stock compressor to a new Sanden unit but I don't know if it really worth the price of a new compressor and I'm not sure if I've to change other parts like condenser to have my A/C properly working

 

[commando1]

Manual A.C. or AutoTemp II?

 

[josehf34]

Manual A.C. or AutoTemp II?

I think is Manual A.C.

 

[commando1]

Does the control panel have a fan speed switch?

 

[josehf34]

Does the control panel have a fan speed switch?

Yes Do you need a pic ?

 

[commando1]

No.
You have a short in the wiring to the fan or in the fan.
Use a Sanden conversion kit from Bouchilon Engineering and youre all set.
You will need to replace the dryer at the same time.
All your fittings need the old O-rings replaced with the green O-rings.
Be a good time to replaces your hoses too because R134a will seep through that old rubber.
For maximum efficiency, you should upgrade your old condenser with a modern parallel flow condenser with 2 pusher fans.

 

[josehf34]

No.
You have a short in the wiring to the fan or in the fan.
Use a Sanden conversion kit from Bouchilon Engineering and youre all set.
You will need to replace the dryer at the same time.
All your fittings need the old O-rings replaced with the green O-rings.
Be a good time to replaces your hoses too because R134a will seep through that old rubber.
For maximum efficiency, you should upgrade your old condenser with a modern parallel flow condenser with 2 pusher fans.

Thanks! I'm going to start looking for those parts. How can I access to the A/C fan to check if there's a short?

What about upgrading to a Auto-Temp II system? I like the idea of a self controlled system

Which parts I'll need to convert my manual A.C.? According to the following graphic seems to be like I only need some extra parts

 

[commando1]

Never ever consider the AutoTemp II system.
People remove them because they are so complicated and difficult to repair.

 

[1978 NYB]

Do your controls look like this?

If they do....you can get your A/C working relatively easy and for a lot less $$$ than converting to a Sanden compressor. Mine gets to 30 degrees at the center vent.

 

[commando1]

Thanks! I'm going to start looking for those parts. How can I access to the A/C fan to check if there's a short?

You have to remove the inner fender on the passenger side.

 

[Big_John]

No.
You have a short in the wiring to the fan or in the fan.
Use a Sanden conversion kit from Bouchilon Engineering and youre all set.
You will need to replace the dryer at the same time.
All your fittings need the old O-rings replaced with the green O-rings.
Be a good time to replaces your hoses too because R134a will seep through that old rubber.
For maximum efficiency, you should upgrade your old condenser with a modern parallel flow condenser with 2 pusher fans.

x2

I did all that with my 70 300 except for the fans. It works pretty good as it is, but I'm putting in two fans this spring.

 

[commando1]

Let's throw a new expansion valve up there on the list.
Be a ***** if you pressurized the system then found out you need a new expansion valve. AMHIK

 

[josehf34]

Thanks guys, I'm going to start looking for some parts the next week

Is a shame that a Auto-Temp II is a bad idea

You have to remove the inner fender on the passenger side.

So, Do I have to remove the passenger side fender and inner fender just to get access to A/C Fan?

 

[josehf34]

Do your controls look like this?

View attachment 69897

If they do....you can get your A/C working relatively easy and for a lot less $$$ than converting to a Sanden compressor. Mine gets to 30 degrees at the center vent.

Yes my A/C controls are the same of the picture. I still not realize how should I remove the inner fender just to get access to the blower motor

 

[MrMoparCHP]

Thanks guys, I'm going to start looking for some parts the next week

Is a shame that a Auto-Temp II is a bad idea



So, Do I have to remove the passenger side fender and inner fender just to get access to A/C Fan?

You do need to remove the inner fender .

You do not need to remove the fender.

Alan

 

[commando1]

I still not realize how should I remove the inner fender just to get access to the blower motor

OK. Go and remove the blower motor without removing the inner fender.
Let us know how that works out for you.

 

[josehf34]

OK. Go and remove the blower motor without removing the inner fender.
Let us know how that works out for you.

Is just I don't have idea how to remove the inner fender and how safe it's to remove it without damage something. I've been looking for bought the service manual online and download it, but I've only found it to be bought and shipped

 

[MrMoparCHP]

Is just I don't have idea how to remove the inner fender and how safe it's to remove it without damage something. I've been looking for bought the service manual online and download it, but I've only found it to be bought and shipped

I have no idea what might be different that the 69-73 but there are a bunch of screws all accessible from within the wheel well.

So first jack up, place jack stand, remove wheel. On the inside you'll need to remove all the screws holding water valves, vacuum reservoirs etc.

This is something that you just need to dive in and figure it out.

Alan

 

[70bigblockdodge]

I would not change the compressor, I would change the expansion valve, dyer, and o rings. The hoses I will leave alone I did not change mine and I am still waiting for the 134 to seep out so I can change a Schrader valve on the back of the compressor. If you change the hoses I would change the condenser to a high efficiency double or triple pass modern one this will take some fab.
My 2 cents fwiw.

 

[livininharrow]

a lot of the afore mentioned advice is good but not totally necessary. pull off your compressor and drain the old mineral oil out of it. measure the amount drained and add poly oil and a little extra. change the o rings to green ones. txv should be fine unless it is already toast. change the filter drier and pressure test system. pull a good vacuum and recharge system. of course you would have to have the equipment and know how to do this. or you could talk to all of your buds and find a good refrigeration mechanic to do this. would take him about 3 hours and a couple of beers. that would be the way to go in my opinion. I have only been doing refrigeration for 40 years.