So today when I tried the AC it doesn't work at all so I took bbyer's advise and took it to an independent land rover shop near me. They took a look at it and just emailed me a quote for $1500. Said that the AC compressor is not working at all and the receiver drier also needs to be replaced. Damn thats not the news I was looking for at all. 600 for compressor, 80 for drier, 60 freon. The rest is labor. I don't know if they will let me install the compressor myself as I can get it online for 350 and 20 for the drier, then have them recharge the system? I will be asking them that question on Monday when they open back up. Any advise from anyone who has changed out the compressor in the LR3?

 

The problem you always run into when you supply parts, do some of the work, and then the rest is up to someone else, when in the end, it does not work, it is still all your problem.

Their markup is to cover some of the costs of making it function if the repair is not as simple as it first appears to be. You will still be nailed for extra money, but is the weather suddenly going to get cool off? I sure prefer a parts solution to black art software being the problem.

I think even a 4Runner would cost the same - while no Toyota owner will ever admit it, that far east stuff does not run forever either.

 

I think you are correct and I should just have them do the work and say a few curse words as I am sitting in the nice ice cold ac on the way home.

 

Ok I just have a hard time paying someone to install something that I can do on my weekend. I ordered the new compressor and receiver drier from amazon. I am thinking of taking it to have the r134 removed and then installing the parts. My question is after I install the parts can I drive it back to the shop to have it filled without it damaging the ac compressor? Of course I would leave the AC off or would it hurt the compressor?

 

The problem as I see it is that the AC system is designed to be never fully off. My understanding of AC compressors is the refrigerant acts as a lubricant. In other words, running the compressor dry may not be the best idea.

The Denso compressor does not have a clutch on it like older style systems where you hear the clicking sound. The compressor is always in operation and there is supposed to be at least 5% flow all the time. The ECONO button is sort of the AC off switch and its operation is described below.

Economy Switch: Reduces the A/C compressor output to a minimum displacement condition x 5%, reducing the engine load required to operate the system. An amber LED in the switch is illuminated when the economy mode is selected on.

 

Thanks buyer. I was afraid of that but hoping if I didn't even turn on the econ and leave it fully off it wouldn't hurt.

 

I suppose the guys you were going to get to do the refrigerant fill would know for certain regarding the Denso, or perhaps the guys who sold you the compressor but somehow I doubt running it dry is good for it.

I did a Goggle using Denso AC run dry as the search term. I ran into a Denso factory PDF directed at the AC installers. I did not know so much could go wrong, but the thrust of the PDF was one has no hope of warranty as their compressors are perfect and there are so many things that can go wrong during the install procedure that for certain, there would not be a successful warranty claim.

Denso seems to make a distinction between compressor oil and refrigerant fluid and overfilling and underfilling either are both bad. Also there was a comment about the compressor seizing during initial run in. That was not encouraging.


As I said, the intent of the PDF was something like ye who buy, abandon all hope.

You might consider getting the guys to include some of that UV dye with the fill. I have LR do that on my top up as I regard the dye as useful regarding future leak detection.

My 1992 Buick had a connector leak that would only appear after about an hour of use; you had to be a true believer even with the dye already telling you where the problem was.

 

That's interesting that the LR3 compressor doesn't have a clutch. Although it is not legal (nor advisable) to release the R-134a into the atmosphere yourself, if you honestly don't think that you have any refrigerant left in the system, you could pick up a vacuum pump and evacuate any water in the system yourself. Alternatively, is it possible to have the shop evacuate the system and then just pull the fuse and/or relay for the A/C before driving it home? Would this disable the compressor completely and allow you to make it home to perform the repairs yourself? BTW, I looked at the cost for our receiver/dryer a few weeks ago and almost had a heart attack when I compared it with the cost of the same part for my wife's accord.

 

Bruce, the oil and refrigerant are indeed two different beasts. There is a specified capacity for both that can be found in the LR3 workshop manual, but when you evacuate the system, typically only the refrigerant is evacuated as the oil is too heavy and/or viscous to be sucked out with the R-134a.

That being said, I can't remember off the top of my head, but there are many different types of oil used for AC systems, and I believe the LR3 takes PAG 46 which is a low viscosity oil. It does get very confusing, because I don't know if any oil should be added back into the system once it is evacuated. If so, I would assume that you want to dose it exactly, so you would want to avoid all of those R-134a cans that have oil/lubricant added to them already.

You can pick up a bottle of the PAG 46 oil with dye already added at Auto Zone and probably most other auto stores. Any store should also have the R-134a with no added oil (I know NAPA sells their own brand) and Harbor Freight has a great price on a manifold gauge set and vacuum pump.

 

Below is what I can find regarding the PAG oil quantities and the R134a quantities.

Regarding me buying AC fluids, refrigeration is something I have never really understood. I continue to hope that the guys at my LR dealership do as with most other fluid related items. It seems with everything Land Rover, how to fill or how much, be it the tranny, the differentials, the AC or even the cooling system is always something one best know what they are doing. I recall a few years back when the LR2 came out, there was much anguish on the shop floor over a tranny oil refill gone bad - it seemed there was no one to blame - neither LR Canada nor the owner.

It just seems whatever techniques I used for years on my Chev's over the years is not quite correct; why is beyond me, but it seems there is always a twist with the 3. This is why with my spring oil change, I always pay them to top of the AC and to date, the system continues to work with no problems which is why I do not know too much about the AC - that is usually how I end up learning the details of any of these things.

While the AC compressor does not have a clutch, there is apparently a frangible shaft within that will snap if the compressor seizes and as such, not rip the belt off the pulley. In other words, a seized AC compressor should not leave you walking.

Lubricant System Refrigerant Specification/Capacity

General Specification

Published : Jul 14, 2004


Item Specification

Compressor oil Denso ND-8 PAG oil

Total system capacity:

Front 130 cm³ (4.5 fluid ounces)

Rear 179 cm³ (5.9 fluid ounces)

Additional amount of oil to be added to system if a component is replaced:

Condenser 40 cm³ (1.4 fluid ounces)

Evaporator - Front or rear 40 cm³ (1.4 fluid ounces)

Pipe or hose 10 cm³ (0.35 fluid ounces)


Item Specification

Refrigerant type R134A

Total system capacity:

2.7 litre - Front system only fitted 550 grammes (10.25 ounces)

2.7 litre - Front and rear systems fitted 810 grammes (28.35 ounces)

4.0 and 4.4 litre - Front system only fitted 600 grammes (21.16 ounces)

4.0 and 4.4 litre - Front and rear systems fitted 900 grammes (31.83 ounces)