FORD "Blue" orifice tube

[76okievette]

Ok, need some help, based on some info in a recent post "Need A/C help in Florida" and since I have the AC system torn apart replaceing some leaking hose's I decide to change the orifice tube in my AC system. The problem is I can't find out where it goes. My system is R134 with a "VIR elimator" installed so the plumbing might be a little different. I have attached a few pic's which I hope someone can understand and tell me where the orifice tube goes. I know what gmjunkie said "located in the inlet of the evaporator at the end of the high pressure line!(small line!!)" but when I open that line there is no orfice tube and the line is not big enough to fit the blue one I have into. Do I have to remove the evaporator cover to but the tube in? HELP
Its a '76' forgot to mention that.

 

[wishuwerehere82]

Sorry I can't help more other than to tell you the GMJunkie's dad passed away, and he will be away for awhile.
As I understand it, the orifice tube is at the inlet to the evaporator. Maybe check the aluminum accumulator cylinder up by the heater box for it.

 

[76okievette]

Thanks, I knew about gmjunkie's dad, Thanks for the advice.

 

[mrvette]

OH hell, I didn't know about his father.....sorry to hear Junk....

take care....

 

[minifridge1138]

Sorry, i didn't reply sooner (and sorry I don't have a good way to post a pic).

The orifice tube is between the high pressure service port and the fire wall. Use a wrench to take apart the fitting, then pull the tubes apart. The orifice tube will be in the hose that goes to the fire wall. I used needle nose pliers to get it out.

I couldn't find a "blue" ford orifice tube from the local parts places (probably could have from a dealer). They had a generic "ford" tube, but Junk had the part number for about 6 different sizes of ford tubes.

Junk told me about an adjustable orifice tube. Somehow, it changes flow based on engine speed. He's never used one, but he said a friend had a lot of luck with them. The local auto parts did sell an adjustable one.

My other advice is to make sure you pull a good vacuum on the system before you charge it with freon. I usually pull a vacuum, let it sit for 30 min, then vacuum it again. During that 30 min, the moisture will boil and fill the vacuum. You need to suck that out as well. I do this for the better part of an afternoon, then let the vacuum sit overnight. If the vacuum is still there in the morning, then the system has no leaks.

Good luck and feel free to ask questions!

 

[76okievette]

Thanks I appreciate the help and hate to be so dumb but do I have to remove the heater box to replace the tube?
I have opened all the lines coming out of the heater box and do not have a tube in any of them.
My, high pressure fill port (the red one) is up by the raditor overflow container.
My system has a "VIR Eliminater" which came with a big metal square part (can be seen in plastic bag in picture) right in the high pressue line, when I take the line off of that I see where its closed down to a very small orfice or opening but its not removable its machined into the metal part.
You can see this in the pic's I posted, is it possible I don't have a orifice tube at all.

installed "Converts A/C system to an accumulator orifice, cycling clutch system as found on late model vehicles. Eliminates the troublesome VIR sticking POA and TXV. Reduces the desiccant breakdown and rust in the steel casing, enhanced by excessive heat from exhaust manifold. Compatible with all automotive refrigerants."
The blue fill port is located on the VIR eliminator and also where the big line from the compress connects. This replaced the "dryer" when I converted to R134.
Going to try and get it all back to normal tonight so any advice would be great. Thanks again.

 

[LVMYVT76]

76 did not have an orfice, the vir takes care of that.

 

[76okievette]

THANKS, I knew there was a reason that I could not find it
Now I have blue orfice tube I can give away if anyone wants it, cost more to ship it than to buy one though.

 

[minifridge1138]

There's your problem!

Hard to find something that isn't there.

 

[76okievette]

Tell me about it, will have the system all back together tonight then a vaccum and charge and I will see what happens!!