Hello all,
I have 1989 Firebird, 305. I need to find out how many pounds of R-12 this system orignally used back in 1989. Any information will be greatly appreicated.

Brad

 

According to theory, there should be a label on the radiator support, or somewhere thereabouts, that should tell you how much it holds. If memory serves (and that is a rare occurance) I think it is like 2 pounds, or so. (starting from empty) I generally shoot some in, and watch the outlet temps in the car. When it gets cold enough for current conditions, I stop.

If your system is empty, don't forget the oil.

 

I want to say my sticker said 2.25lbs, but I don't remember for sure. I don't have it anymore

 

I have no sticker anywhere..I will start with 2 lbs and go from there.

thanks

 

look on the blower fan housing. It's under the hood, right by the radio antenna. That's where your refrigerant label should be.

My 89's sticker says 2.25 lbs. Early thirdgens took 3.00 lbs. starting around 87 or so (i think) they went to 2.25 lbs.

 

no stickers there....anyway according to GM Service Manuall, the R-12 system held 3.5 pounds, guess I should have looked there 1st before posting.

 

I was going to reply and say that's surely too much, but...

I too have a gm service manual and looked it up. It does say 3.50 lbs. I double checked the decal on my blower housing, and it says 2.25 lbs. Now I'm not one to argue with the factory service manual, but that has got to be an error. 3.5 lbs is a LOT of refrigerant. The last time I put more than 3 pounds of R12 in anything, it was a Suburban with dual AC. I 'm not sure what to say here, but I would strongly suggest charging to 2.25 lbs and checking performance.

 

I started with 2 lbs and will check tomorrow, understand that I had to convert to R-143, but I just got the EPA 609 cert and will most likely purchase some r-12 and put it back in the system, with a new compressor and drier. I can never get the R-134a to get the bird cold. I know there are alot of opinions out there, but I look at as this system was designed for R-12 and I am going to try it and see if I can get some decent cold air.

 

there is no advantage to R-12 over R-134a. Just use the nature-safe stuff, man. It's cheaper and easier to get.