I seem to have a very small leak of refrigerant from the low side fill port valve, I can get a tool that allows valve replacement without discharging the system but I need to know what valve style the FD uses - "Standard" (Schrader) or "JR4". JR4 is a slightly larger size valve. Anybody happen to know which one is used for a 134a system? I can buy a tool that does both but it would be nice to know in advance and save a few $$.

 

Unfortunately I doubt you can find this out, I know the ins and outs of the FD's AC pretty well and I've NEVER seen this info anywhere. I could be wrong though!

But if you do find out post it up! I'm also interested in the tool you found to swap the schrader valve.

Dale

 

My 1995 had an R134a system (don't have the car anymore). I topped off the refrigerant with one of those auto part store cans that has a low side pressure gauge. I assume it's a standard fitting then.

 

The more I look at it, I think the valve used is the standard Schrader version, not JR4.

This tool is supposed to allow removal and replacement of the valve without discharge of gas: There is one that does both styles of valve for about $30 more, that may be the better option for futureproofing.

I was really happy to learn that this kind of tool even exists, the last thing I want to have to do is discharge and open my car's AC system to the atmosphere just to fix an micro leak...as I understand it, my car has one of the not-available receiver dryer designs...

 

My March 1992 R1 FD had the MANA AC. I replaced the two stock R12 ports with the R134 ports conversion kit sold at AutoZone a few years ago.
This was done when I converted from R12 to a 12/134 replacement gas. The two valves are small.
I am currently having a custom condenser coil installed along with the later design R134 drier.
The lines for the drier are from a 1996 Mazda Protege. Visual site port line also has a built in port. It uses a large valve.
See picture.

 

To follow up on this: Using the Mastercool extraction tool, I was able to replace both high and low side valve cores. They were the "standard" Schrader valve core (the valve on the bottom of the photo posted by @cewRX7r1. I also checked my wife's 2011 Saab and the cores in that car were also slightly leaking, in this case the low side a standard and the high side one was a JRA. Again, the tool worked great, changing the cores took less than 5 min on the Saab (longer on the FD as a couple hoses need to be removed to clear the high side port area.

If you have this issue, the Mastercool tool is a lifesaver, virtually no loss of refrigerant (just what filled into the tool), and more importantly, no need for a visit to an AC shop. Already has paid for itself x3 for me.