Mercury villager 1994 location of A/C orifice?

I am looking for the A/c orifice in the condenser/evaporator line on a 1994 Mercury village with an auxiliary A/C unit.
Mercury villager 1994 location of A/C orifice?
On line coming out (near bottom) near the cannister by heater box, - (the thingy that always was sweating while a/c was working)! Is about 3 inches from heater " box" at firewall (called a plenum)!! There are 2 lines about 3/8 inch in diameter tied together with metal piece with a screw thorugh it holding it together! Come back toward front of engine about 6-8 inches, and you will see fittings there (2 different sizes 11/16 and 7/8 as I remember)! Hold these fittings securely to prevent bending tubing, _ -- you will see that the one going towards firewall has a "reduction in size"--the orfice and "finger screen" are in there! This is located on the"high pressure" line, (smaller line coming from the compressor). Of course you have to evacuate the system, -- and it is sometimes hard to remove screen from the tube- use anything that you can hold on (possibly a hook)-and pull out --if needle nose pliers aren't able to grip it enough!








And if there is a bunch of the dessicant from the cannister in there plugging it up, - then the cannister needs rerpalced too!





Contrary to what manual says you don't need all the equipment they say! It is a "critical charge system", - the exact reason why you are now needing work,-- (it is the cheapest working system available) -- and will need much work in future as you use the vehicle during it's lifetime!.... 1/2 pound too much or too little "freon " will make the unit inoperative!





Once system "pulled down in vaccuum", - you can charge system with only "low side hookup and no gauge if it is nescessary, -- gauges are nice, - but system will tell you when it it s full! I did theis by observation and experimentation, and actually got better results than going by the book with "calibrated" meassuring system etc! You see, the vehicles aren't always textbook" all the time, the hoses may be a litttle longer, and a little bigger inside , - and in case of vans with second system put in rear, - that really messes up calculartions!





So here's what you do,-- you start engine, turn a/c on "full blast", open all the doors, , - and block pedal on gas down, so it runs about twice (or a little more) faster than regular idle... (this makes compressor run fast enough to put out full performance! Now you start adding freon (R-134A)-- you may have to remove plug on "low [pressure switch" (if so equipped), and short between terminals to make compressor run for a while -- till pressure comes up enough to hold it closed! The compressor will "short cycle" very rapidly till you start getting near full, -- then it will start staying on longer and longer -- till it is around 45 seconds , -- shut off flow of freon for a couple minutes and allow compressor to cycle 4-5 times to equalize pressures! Now watch top of cannister and see condenstation forming (because of cold), -- add freon till you reach 60 seconds, stop and wait for a while-- watch top of cannister, - it will "flash frost" on top when it is working the coldest it can possibly get! --- beyond this point the compressor will start running shorter times again! This is how you can tell it is overcharged! If you continue adding freon, it will shorten down to short "run cycles" of clutch again, -- just like when it was out of freon! As to the condensation, --if really low himidity day,- it may not have any water in air to condense! You can put a little on it to watch, -- or do as I always did, just hold palm of righ thand on it, -- when it becomes unbearable to hold it there anymore you are pretty close to freezing!





I leaerned this in the mid 70s when they first came out on Gm vehicles! I worked for a Midwest a/c distributer that covered 4 - 5 states, - we installed "'after-market" units on new cars, (as they worked better than factory ones)!! And as shop foreman, and service manager I had to be the "in-resident expert" when all these dealers could not get this "new-fangled stuff" to work! We had them hauling them if for better than 500 miles to get them fixed (we made a bunch of money in a couple years)!!





If the auxiliary unit has same kind of unit, - it will look about the same but be near the unit itself (but in rear of vehilcle) I guess, -- if you are lucky the rear unit will be much better unit than the front and have a"thermal expansion valve"! This then would be an "old fashioined unit" , which is entierely different! I can't say exactly, as I have been out of that line of work for years (except on my own stuff)!