Air Conditioning leak 97 Blazer 4.3

06-14-2011, 08:19 PM
My daughter's 97 Blazer with 4.3 has been leaking R134 for some time. I have had to recharge it twice a season for the last couple of years. Now it seems like it barely lasts a week I am trying to determine where it is leaking from. Are there any components/locations that are more likely to leak? I have seen a post or 3 that mentions the evaporator and the compressor seal and or the case of the compressor..anyone have experience with this..all input welcome


Blue Bowtie
06-14-2011, 09:09 PM
Case end seals on the Sanden compressors are good for about four years at most. The design is very poor. Even the Frigidaire R4 compressor was superior. Unfortunately, you are stuck with the design since there is probably no room for a good compressor in the mounting brackets.

If you are lucky, you can find a domestic remanufactured unit which might actually seal better than the basement of an eastern nuclear power station.

06-14-2011, 09:20 PM
They should make a can of freon that has die in it to help find your leaks. Walmart use to carey them but if they don't anymore then check at an automotive parts store.

06-15-2011, 08:59 AM
It has always seemed to me like the case of the compressor had an oily film that would build up on it. I assume that this is could be from the case seals you are refering to.

I have not run ultraviolet dye through it yet...but I can this weekend.

Is there any sense in replacing it with a used compressor from a junkyard?

Is there a quality aftermarket unit that you would recommend one that is not too expensive.

With this being a 97 I'm thinking that if we can get 3-4 years out of a less expensive option it might be a good way to go.

Did the manufacturer ever improve the design in later years? Like if I got a compressor from a 2002 or 2203 (assuming they take the same compressor) would they more likely be an improved design?


06-15-2011, 06:59 PM
Most of the aftermarket compressors I've bought from Auto Zone, Advance, etc have never held up good but if you can do all the work yourself you can save good money. I would not buy one from a junk yard cause unless it was coming off basicly a newer vehicle your just buying someone elses problems. And with this being a 97 model thats not looking good. I don't know how much a dealer gets for a remanufactored but that may be an opition or maybe someone else on this forum may know of a good after market brand. First make sure it is the compressor. And they do make freon with a stop leak in it to help on smaller leaks. If you go that rought and it does not work make sure you flush the system real good and change the filter before you put new parts on it.Good luck.


06-15-2011, 07:55 PM
Pinpoint the problem with a 134a leak detector from Amazon!
Because of Age, suspect the schrader valves.

06-16-2011, 09:18 PM
The original equipment compressor on your 97 Blazer was a Harrison HT6:

They are known for leaks commonly referred to as a "belly leak", (the seam around the center of the compressor).

Blue Bowtie mentioned a "Sanden" compressor:

The Sanden is designed differently from the Harrison and has a one piece crankcase, a far better design. I also agree about avoiding junkyard compressors, unless you find a Sanden! Install dye in the system and confirm the leak before you replace any parts.

06-17-2011, 12:50 PM
Mine was the Harrison. I was able to get a junkyard unit from a 2001 for free. I installed it last night. Pumped it down good with my vacuum pump let it sit for 10 min. no drop in vac. recharged it added 3 oz. oil and a 1/4 oz. of dye. I hope my only problem was the o man was the bottom of the old compressor covered with crudy buil-up from the leak..I couldn't get a drop of oil to come out of it either...guess it leaked it all out. wasn't hardly any 134 left in the entire system either. I' sure your right about the quality of the used junkyard units but since it was free, and I knew my old one was bad..i gave it a shot

Thanks to all


06-24-2011, 02:03 PM
Checked it with leak detector black light looks like I'm goOd

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