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73-87 Chevy _ GMC Trucks => 73-87 Chevy & GMC Trucks => Topic started by: Bucks87silver on June 21, 2006, 11:39:00 am

Title: AC rebuild
Post by: Bucks87silver on June 21, 2006, 11:39:00 am: 87 chevy K-10, 350 w/stock ac unit. Recently converted to 134 and charged the system myself to the 3.25 lbs it calls for (I have no gauges) and just went by the weight content of the cans. The compressor will engage quickly on/off/on and I begin getting cold air. However it doesn't maintain the charge and I've added a can or two over a couple of days only to get the same result.....minimal, and assuming I have a leak. I've never messed with an ac system before and wondering how difficult it is to replace O-rings and seals or whether I'd be better off having someone with the required tools do it? Any tips or advice appreciated.
Title: Re: AC rebuild
Post by: VileZambonie on June 21, 2006, 03:44:00 pm: 1st of all when you converted it did you vacuum the system? when you charged it did you add oil? A can of pressurized dye tracer and a uv light will help you pinpoint the leak. You can buy a kit at autozone.
Title: Re: AC rebuild
Post by: Lt.Del on June 21, 2006, 07:17:00 pm: The system will have to be totally evacuated by a shop that does that.

If not, once you break open a line, the pressure will knock your socks off! Not to mention it is illegal and will mess up the atmosphere for my children.

After you evacuate the system, the o rings aren't bad, you just gotta know which one to replace. They just slip on and off.

I usually keep a package of dozens of miscelaneous sizes with me.

As VileZombonie said, the system will then have to be completly vacuumed until it holds under 29.9 for a period of time. I do that several times to ensure all the moisture is boiled out of it. If it doesnt hold the vacuum, you haven't fixed the leak.

And, as mentioned, get that oil with the green dye.

SgtDel
aka "Andy"

www.delbridge.net

1979 Big 10 383 stroker
1991 Blu 'Burb 3/4 ton 4x4
Title: Re: AC rebuild
Post by: Bucks87silver on June 21, 2006, 07:48:00 pm: Hey, thanks. Yes, I did use one large can of 134 with the oil additive. I should have used some dye. The system seems to work fine....... temporarily, but must definitely be leaking. I figured the o-rings would be no big deal but I don't have a way to evacuate so it looks like a shop job.