I have a 97 Marquis, about 2 yrs ago I bought this from a dealership that did a quick recharge for me on it and it worked for 2 summers, then faded out... I went to the store and bought a recharge kit but I don't know where the port is to hook up the gauge/refridgerant tube.


I found two spots I think it could be and i snapped some quick pics and circled the area in question in red


http://radiowars.homestead.com/airconditionerline.html



If you guys could look and let me know if either of these spots is the correct one I would greatly appreciate it. Again just wanting to find the low pressure service port to add refridgerant and check pressure of a/c system on a 97 marquis.


Both of these seem to be located on the passenger side one in front area one in rear area (pics help in link above as to the two places Iam guessingit may be).


Also if neither is the proper place to put the gauge/fill tube onto please advise me where I can locate this on a 97 grand marquis.


Thanks,





Bill

 

There are two service access ports on the air conditioner system. Both have a quick connect type of fitting with an internal schrader valve. On the forward one, it should be a larger diameter fitting than the one to the rear.[ 16 mm od ]Front one is connected to the high pressure side of system. Rear one is located on the suction accumulator which is on the low side of the refrigeration system. It should be a slightly smaller diameter that the one on the front[ 13 mm od]. To recharge the system, you will need to recover[remove by another piece of equipment] any remaining refrigerant in the system. Evacuate the entire system using a vacuum pump to remove any non-condensible gases and moisture. Pump system down to 29.50 "Hg for at least 30 minutes. Then add refrigerant to the system through the low side until pressure equalizes. Start the engine, turn AC on full cold and high blower with windows open. Compressor will start andcycle on and offuntil pressure on low side of system will maintain 25 psig or higher. Correct weight of refrigerant will be located on a label under the hood. Continue to add refrigerant until correct weight has been met. Correct operating pressure for about 90 degree ambient temperature should be about 250 to 270 psig on the high side and 35 to 40 psig on the low side. Outlet temperature at the louvwers should be about 35 to 40 degrees less than the air in the vehiclewhen cortrectly operating. Once recharaged. Stop engine. Remove any connection fittings and replace the sealing caps.