We've owned our 95 Trooper since new and now (I assume) the freon seems to be gone. I'd like to tackle this myself - can anyone help get me started? Does this stuff leak or wear out after 11 years? Is just a simple recharge the first step - I've never done that either.

Thanks.

Im not sure what the regs are where you are, but here in Pa you cant even by the freon without being licenced. If the freon is gone, it pays to have them do a leak check first, (they will put a dye in the system. to find the leak,) It may be relay related also, on the 96 rodeo i had, theres a small canester behind the grill that i just jumpered the two wires to get the pump to run. If the freon is too low, it wont kick in automatically. atleast this way you could tell if its your pump clutch.....

First thing to do would be to put a set of gauges on there and see if you have any refrigerant in the system. If you do, then it's time to look at the a/c clutch and make sure it's working. Then things like the pressure switch, etc. If you don't have any refirgerant, then it's time to look for any obvious cracks, broken lines, loose fittings, etc. If you don't see any, then I'd pull a vacuum on the system to see if that helps you find where the leak is. If the system is r134a, which I'm 99% sure it is, then you should be able to do this all by yourself. If it's r12, then you'll most likely have to have someone do it for you if you don't have a license to purchase r12.

Richard <img src="/forums/images/graemlins/patriot.gif" alt="" />

just to check FEA ;

you know that the a/c compressor clutch is clicking in? in other words, when you push in the A/C button and turn on the fan, you can hear it engage?

just checking, because there are cases where this doesn't happen for a number of reasons (electrical and electronic), and it appears that the ac has lost its ability to cool, when in fact it isn't actually working.

that said, it is also true that it won't engage if the refrigerant pressure is too low.

Just wanted to add that if it turns out that there is no refrigerant left in the system then you will have to have it put under a vacuum by a shop before recharging it. This also applies if you remove any part of the system to repair a leak.

And no, refrigerant doesnt wear out over time. It should never 'run out of gas' either (heard a grease monkey idiot tell a customer once that their system had just run out of gas).

At this point I'm sure I have R134a, and that the clutch is engaging when I turn on the AC. So, in tackling this myself, the pressure gauges you mention are the first step VS a leak test? Are these something available at the parts stores?

The manual has a thorough trouble shooting guide using the pressure gauge method, but no leak test details - though they mention looking for leaks. I'll certainly check to see iif there is anything obvious first.

Thanks guys.

I was in O'Reilly Auto Parts the other day, they have a kit for $20 that has some refrigerant and some dye along with a set of yellow glasses and a UV pen to put into your system. I have a leak in my newly converted to 134a Dodge Shadow and I plan on getting this to figure out where my leak is.

The gauges in those kits arent usually very acruate. Also the refrigerant that comes with them usually has seal expanders in it and will kill the compressor. Alot of ppl call them "death kits". Plus they only look at the low side, you really need to check both high and low sides. Harbor freight has a set of real gauges on sale right now for $30 http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=92649

I believe it tells you on the info sticker under the hood what freon you have in it.

It's pretty easy to tell. Screw on fittings, r12. Quick disconnects, r134a.

Richard <img src="/forums/images/graemlins/patriot.gif" alt="" />