Technical > Automotive > [Help] AC Pressures

reply to dolphins

Re: [Help] AC Pressures

Yes, I know the gauges are old. I had to retrofit the gauges with R-134A quick connects. Without researching it myself I was told that the replacement for R-502 (the outer most scale in black) was similar in properties to R-134A and can be measured the on the same scale.
--
Stop The Mindless Killings Stop Over Fishing

reply to Beezel
All that matters on a gauge is the pounds. A PSI is a PSI. Ignore the temperature scales if you're not using one of those refrigerants. (And don;t use those on a 410 system.

I cannot see your video for some reason, keep getting an error. What do the pressures read when the clutch is engaged and running?

Thanks Buddy,

I converted it to .wmv so you should be able to view it now.

You are undercharged. Leak somewhere.

That's what I told the mechanic out at Holman Ford. They put the dye in it and couldn't find the leak.
--
Stop The Mindless Killings Stop Over Fishing

It would be a sizable leak to lose that much refrigerant in a month. Also, the system needs to be used for the dye to mix with the oil and the oil/dye to get to the leak.
If you have access to a standard black light you can search for the dye yourself as it should light up nicely with a black light.
--
mbsastronomy.com

reply to dolphins
Don't forget to check the service ports with the gage set removed. I have seen the lines rub through where contacted other metal, and, as big a pain in the ass it is, you need to tear the dash apart and check the evap coil and connections.

I was just reading where the evaporator is located. Crap, that's probably where the leak is since no one can find it.

My thanks to both of you.

I'll be sure to update when I find the leak.
--
Stop The Mindless Killings Stop Over Fishing

It is possible to find evap leaks without tearing the dash apart. If you can see the drain hose, sometimes the dye will show up inside the tube or on the firewall where the water drips down. Another way is to put a piece of cotton ball inside the tube, it will trap some of the dye in the cotton and you can check it. Remember, the system needs to be used to help get the oil to the leak. Also, adding some oil to the system may not be a bad idea as well.
--
mbsastronomy.com

Just realized I wasn't subscribed to this thread anymore after the ole switcheroo.

I did go over the engine compartment with a black light but found nothing. The only place I saw any bright neon greenish yellow residue was on the low-side tap and accumulator which is consistent with the recent recharge. I did it at night so the whole engine compartment was illuminated in black light. FYI, bugs love black lights. It's time to find a AC tech and not just a mechanic. Even if I do find the leak, I don't have the equipment to do the repair.

I'll post back when it's fixed.
--
Stop The Mindless Killings Stop Over Fishing

Valve cores can fail and leak. How much dye leakage were you getting from the low side service port? You could also attempt to clean it and see if the dye reappears.