Anyone know what type of Schrader valve the A/C system uses?

[Retiredwarhorses]

It does engage and disengage with the switch so the clutch is working. But yes, it would run even with no pressure in the system. It does blow nice cold air. Around 20 psi low side and 110 high side with 65 degree ambient temps.

its doing this with No r134a and no shraeder valves? Lol

 

[diesel_dave]

its doing this with No r134a and no shraeder valves? Lol

Correct! That's why I never suspected that the valves weren't installed. I figured there was at least enough refrigerant to kick the compressor on. I only figured out what was going on AFTER I removed the manifold gauge connections after filling the system with r134a. That's when it all exploded right back out in my face and I figured out the valves were missing.

 

[Action]

Thanks for the help everyone. I found the type of valve core that fits. It's the small style that you can find at any auto parts store. I didn't think it was right at first because it looked like it would fall right down the hole. I carefully lowered one in and it threaded right in no problem. I ordered a manifold set and vacuum pump on Amazon just for this and I'm glad I did because I've had to vacuum it down like 6 times so far. Since I didn't know the valves were missing this whole time, it was definitely open to the atmosphere for probably years. Thankfully its been nice and dry at Yermo and it's dry here in Utah. I vacuumed it down and it set at like 25 in Hg for over 24 hours so hopefully most of the moisture is out by now. I guess I'll just run it until something blows and then go from there.

Is 25” enough vacuum to get rid of moisture? I thought it had to get to 28-29”.

 

[diesel_dave]

Is 25” enough vacuum to get rid of moisture? I thought it had to get to 28-29”.

I live at nearly 5k feet altitude so that's really about as much as you can get.