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A/C working for short periods of time

SnowDrift said:
When you say system rebuild, do you mean new compressor, orifice tube, or do you mean evaporator and condenser, as well? I found a local shop that says they can do a system flush for $50, but what am I looking for, specifically? I will go to their shop first and have them show me what they do and what they use, but at this point, I wouldn't know what to look for.
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Again just by the "it's noisy" comment is a bad sign. Make sure it isn't belt noise you are hearing.

Rebuild is a compressor, orifice tube, accumulator, flush, oil, recharge and possibly a condenser depending on design and debris.
Like I posted above, the best way to tell is to look at what is in the orifice tube screen.
 
Also if you need a condenser get one for a dual air Burb. Its bigger than some trucks and still fits like factory. Did it on my 94. Dont know why, but that was the best a/c I ever had.
 
Since I'm probably looking at replacing the compressor, I'll have the system evacuated and will plan to do the work myself. I'll have no need for A/C until next May/June, at this point. Is it a bad idea to have the system sit "empty" over the winter, or should I wait until next spring to do the evacuation and start replacing parts at that time?

I think I'm leaning toward a Four Seasons pump. I'm not really interested in fabbing brackets for one that doesn't fit in the stock location. Any suggestions?
 
As long as its sealed should not be a prob. Any possible moisture should be burned off when you evac it next season.
If comp is brand new it seems they (R4) last about the same IMO. No rebuilt's!
 
I would wait till next spring to evac it. It is always best to let it sit with pressure in it as it reduces the chances of moisture getting introduced into the system.
 
Can I disable the pump by pulling the fuse in the dash (assuming there is one there or under the hood)? I will still have a use for the defrost in the cold months, but don't want to run the compressor.
 
Unplug the compressor or the low pressure switch, either will disable the compressor from running.
 
WarWagon said:
The New ones are all the same - biased on a marginal for R12 design. NOS (new old stock) Harrison would be the best with everything else being 2nd. Four Seasons is at least made in Texas and AC Delco could be made anywhere including the same Texas plant or China.
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Good info. Thanks. No commie parts if I have a choice.

Harrison is what I bought for it, originally.
 
I bought a 4 Seasons pump - Made in USA. All I could find was a commie accumulator, though - not real happy about that. System took around 3 lbs, for some reason to get it right. They tried to get 2 lbs to work, but I guess it didn't. They ended up flushing out a bunch of crud, too - probably from the pump coming apart. He said to keep an eye on the temp once it's warm out and let him know if it needs to be looked at again if it's not blowing out at 40 deg.
 
SnowDrift said:
I bought a 4 Seasons pump - Made in USA. All I could find was a commie accumulator, though - not real happy about that. System took around 3 lbs, for some reason to get it right. They tried to get 2 lbs to work, but I guess it didn't. They ended up flushing out a bunch of crud, too - probably from the pump coming apart. He said to keep an eye on the temp once it's warm out and let him know if it needs to be looked at again if it's not blowing out at 40 deg.
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It's 2 or 2.25 lbs, if it took 3 pounds that means they most likely didn't get enough oil in the system. You charge by weight, and if your head pressures are low it needs oil, if they're to high it has to much oil in it.
 
SnowDrift said:
Thank, Ferm. I'll ask about this when I talk to him again.
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The other thing it could be is they could have used PAG 46 oil instead of PAG 150. GM used PAG 146 or PAG 150 for there earlier A/C systems, and when switching to PAG 46 like most modern compressors use I have had to adjust teh charge and oil amount some to get things working right.
 
I ended up taking my truck back to have him look at it again yesterday. He checked it out and said if it was his, he would leave it right where it is, right now. The air temperature was at about 54 coming out of the vent on MAX, with the engine around 2000 RPMs. I think it was 76 inside his shop.

He did mention, though, that if I would like the orifice tube changed out, I can have that done and he might be able to obtain better results with a different size. He said he's done that on a lot of ambulances in the area. I told him I think I'd just leave it as it is, right now and we'll see how it acts once we go on a trip. It used to freeze me out and I have never ran it on MAX since I've had the truck.

As I think back on this, though, maybe that's the reason for the premature pump failure, due to incorrect levels and the pump was overworked?

I did mention the oil type, but he did say he felt the accumulator was different than the OEM part I had.
 
If you were closer I would help you, but your a bit of a ways away. Something isn't right with it as mine will steam out the vents on a 95 degree day. I have NO problems with getting 45 degree air out the vents, and it will normally drop down into the 30's even in mid 90 degree heat. I run mine on outside air, running down interstate at 70, and even with dual air mine blows mid 40's out the vents. If it I put it to inside it just cycles on off and on because it gets to cold. He either messed up the oil charge, the refrigerant charge, overlooked something in the system it may still need(bad condenser, if you have a compressor failure the condenser MUST be replaced), or you got a bad compressor. Theres no reason you shouldn't have air in the mid 40's coming out of the vents unless you have a blend air door not working allowing airflow through the heater core.
 
SnowDrift said:
What is the reason for the condenser replacement being a must if the compressor fails? Blockage?
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Yes. The stock OEM condenser is a flat capilary tube, and it cannot be flushed out. Once it gets trash in it, it's there. Also they can easily be partially blocked due to the nature of a flat capilary design. This is why most of the replacements have now gone to a round multi pass style condenser. They are more efficient, can be flushed out if contaminated, and are smaller than the OEM design(thinner and allow more airflow through them).
 
Ok. I'm looking at this, below. I will call to verify whether it's made in the USA or not. I'm not opposed to replacing it if it's the right thing to do. I caught a video, too, that was talking about the same thing - replacing if the pump goes.

The condenser that is in it may or may not be an OEM part. I know I replaced it, but cannot recall if it was a Delco part or not. I am thinking it may have been something aftermarket.

The style condenser you're describing - is there someone making this for our trucks, or was that just a general statement? The ones I look up all look the same, physically, according to the pictures.

http://www.andysautosport.com/chevr...hvac/air_conditioning/silla/sila00001707.html
 
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