I think that's why I haven't replaced my heater core in my truck yet. I just keep adding more things to my list. By the time I end up actually doing it I'll probably have a whole new AC system. lol

Hopefully for him it's just the valves and maybe the o-rings.

 

It's called "Scope Creep"..... Or, "While I am in here...." syndrome. I suffer from that too.....

 

Yep it was empty. Now I want to test for other leaks. I don't think that valve was leaking before I pugged into it. So it is a problem now, and I will replace it.

 

Second question is how to properly jump the compressor. I was able to get it to come on by fiddling with the pressure switch connector. Now that only works for a second, then it cuts off. Not long enough to build any pressure. That brings me to my other question. If you suspect a leak. How would you fill the system to test? I put a couple of ounces of pag46/UV in hoping it would be enough. That was from empty. So that is the only thing in the lines after I vacuumed it in. Should I also immediately add more 134a???? Not quite sure how to circulate the UV without blowing more 134a into it. I also don't want to blow it all up!

 

For future reference, assuming I get all the leaks worked out. I need the total fill info. I saw another post that said my truck should have 6oz of pag46 and 1lb 6oz of r134a. Is that correct?

 

Pull a vacuum on the system, see if it holds. If it doesn't, might have to waste some R134 with dye to find it.

 

1. Does vacuuming the system remove the pag oil as well as the moisture?

I put a couple of "new" ounces of pag oil with UV in and don't want to overfill it with oil. Since I have only replaced the schraders and vacuumed it, I am unclear on if it has any original oil left in it.

2. Where can I find the PROPER refill quantities for 134a and pag oil for my truck??

My truck 2008 1500 5.7L has NO sticker on the hood and the stickers above the radiator do not mention the ac system. I have been searching google for hours and only found one video that mentions quantities for my truck. Not sure I can trust it.

TIA!

 

The oil shouldn't evaporate under vacuum.. I don't think.....

Get yourself a Factory Service manual for your truck. You can generally get a PDF copy for 30 to 40 bucks.

 

Well I went ahead and filled it with r134. Now it blows cold. Gauges read 39/175 L/H psi. It took just under 24oz. The pag46 oil question remains. I either have too much, or not nearly enough. From empty, I put in 2 oz, then vacuumed it, then filled it with r134a. Assuming that some oil remained in the system after nothing but a schrader change, maybe it is ok. But if vacuum removes all of the oil, I am low on oil. Really low. Really hope someone who knows sees this and can chime in. I don't want to run this much if it is low on oil. Seems like a really bad idea.

TIA

 

Thanks heyyou, I have that manual somewhere. But it is packed away since my last move and I have another 50 boxes to open. I was hoping someone had easy access to the info. Not sure it would address my questions about oil either.