After 4 trips to the dealer for a non-cooling A/C, they FINALLY pinpointed my problem. My schraeder valve leaks. The tech said that I was only down about a pound and a half but apparently thats enough. They charged it in early June and it lasted until about mid-August. It seems that that valve is part of a LONG solid tube running about $400!

Do I have any other options? If I had access to a R134 charge system, could I conceivably do the job myself?

 

Take it to a regular A/C shop. You can get a much better price than that. Schraeder valves many times will seat properly if they are equalized. I have seen those leak before but by putting a cap on them to seal valve the pressure inside the cap will help to seal the valve. By the way my 98 takes around 32 to 34 ounces (it is on the label on the truck). If you were down a pound and a half that is 24 ounces. That is not a little bit.

 

Also, unless I am wrong, can't you replace just the Schrader valve core?

Check out a real parts store, you should be able to buy the AC line set far cheaper than 400 bucks in the event the valve is non-replaceable.

And yea, a pound and a half is a ton, it shouldn't have been cooling at all with that much gone.

 

The Schrader valve core is specifically for keeping the refrigerant in the circuit till the tech can connect his service manifold. The cap is what makes it gas tight. Just like the valve stems of your tires.

Period.

You'd do well to find another service tech as that fella's full of stinky.


On that note, check the cap(s). If it's a solid metal cap, it is intended to be torqued down so as to have a metal-to-metal seal. If it's plastic, there should be a rubber O-ring inside for the sealing.

(Going on 20 years of professional service and repair of HVAC & Refrigeration).

 

Yep - most of 'em are either cracked or missing - clean out the port, crank it up, put a can in at about 2000rpm, add a new cap, and yer good to go...................

 

When a schrader vlv leaks it's usually because it's loose, just tighten it with a tire vlv tool, not too tight. As already stated it's the vlv CAP that does the sealing and the plastic ones seal better so long as the seal is in the cap. Note there are always 2 schrader vlvs one on the lo side and one on the hi side. If they say the line needs to be replaced it could be because someone stripped the threads. The lines are not that expensive, if it's the line with the schrader by the rad, that one contains the expansion tube, I would NOT use a used one. Retail was about $125. The lines are different from a gas truck so harder to find.

 

standard schrader valve tools don't work on 134a automotive fittings. there are tools and replacement valves available.

 

Thanks Duner you're right. Ive been retired for awhile and was so used to seeing the retrofitted R12 to 134a fittings. To be honest I usually hook up the 134a gauges, lock them on, open them up and never pay any attention to the vlv. Just goes to show you're never too old to learn.

 

The low side has a "schrader" valve. The high side has a ball/spring style and does not show as a separate part number under the parts listing for trucks.....however, it uses the same part as the Dodge Neon has and it's available as a separate piece.