I have a 2000 DII where the air conditioning makes no appreciable difference on a hot day. I may have a leak somewhere.

I plan to take this vehicle on a trip down south and the deciding factor between taking this vehicle or another, is whether or not I can get the AC functioning.

I'm just looking for some pointers: where to start troubleshooting the ac on this vehicle, what are the common failure points, and if you can point me in the right direction?

So far I have done the self-diagnostic test (two buttons depressed while turning the key). It gave me no errors. I tried adding refrigerant twice: it emptied the can in less than a minute. While charging the refrigerant, I could hear the compressor kick on. When the can was empty I heard the compressor shut off. Also, I noticed that while the recharge kit was open there was no residual pressure (I could squeeze the can just like an open pop can with the valve open).

 

Sounds like you have a leak. If one can got the compressor to turn but then it stopped, you are probably still low. You can try adding another can but get one with the little gauge on top so you can check the pressure. If this gets it blowing cold, you still have to find the leak. If you plan to find it yourself, go ahead and add a can of die before the second can of refrigerant.

 

I should probably remain silent since I'm not an A/C expert by any means but A/C is one thing I'm willing to pay to have done.

If you have that big a leak you'll likely need a new receiver-dryer, to be installed only after the source of the leak is identified and fixed. You'll need to have vacuum pulled to evacuate the system and then have the correct amount of refrigerant replaced. If you don't have the right equipment it's a fool's errand.

Yeah, I've read about people pulling a vacuum with improvised equipment but for A/C I leave it to a pro.

 

Those cans flushed out of the system pretty quick. So my guess is the leak is "fast" because it never got the chance to blow cold air.

Do you guys think this is something worth handing over to an AC shop? I was hoping I would maybe identify a bad fitting or pipe and fix that portion myself to save some money. I'm worried that this could easily be a $500-1000 fix.

The recharge kit I have has a pressure gauge on it. It shows positive pressure on other cars when hooked up.. but on the rover it would only show positive pressure when charging.

 

Needs dye ran through it.
Then a black light to see where it leaked.

 

Add dye and go from there. If your lines look decent then it's most likely an o-ring at the compressor or firewall. Easy fix, the dye will point the way.

​​​​​​once you've fixed the leak you can pay to have it evacuated and recharged. Don't attempt to refill it with the cans from the parts store. Not only would this cost a fortune, but they add oil as well and too much oil in the system is bad news.

 

+1
There is a certain amount of lbs of freon that must be added, and not over filled.
Parts store canned freon cannot be easily or accurately measured.
As said, it needs proffesionally recharged for best results.

 

On top of that, those cans of r-134 are like $40 a piece. if your system is completely empty, it would take like 10 cans to fill it.

​​​​​​I would do all the repairs yourself, but better for a pro to handle the evacuation and refill.


​​​​​​Edit: actually it looks like discos have a relatively small capacity. That's odd, just a little over 2lb of refrigerant. I'm used to 6-8lb systems. Either way, evacuation is necessary.

 

What size? Around here, 12oz cans are less than $5 ea now. From bone dry, 3 cans should do it.

 

Yeah I was mistaken on my capacity. 25oz total is a lot smaller than I'm used to. Regardless, you want to get all the oil out before refilling and accurate filling is better achieved under vacuum anyway so better to just put it on the machine rather than risk adding way to much oil and possibly way to much refrigerant as well.