Air Conditioning

[cmkelly]

Hey Gang,

Has anyone ever serviced their AC? Mine just quit blowing cold yesterday and I wanted to poll the group before I took it to someone. Is it the cheap do-it-yourself variety or the newer expensive type?

I know most of you purist have either taken your AC out or always ride with the top down but when it's 90 + degrees it sure is nice..

[waitn4sno]

AC?? You lucky dog!!I did not think any Vert's were built with factory AC??First things first: Check pressure - no pressure = no freeon = leak If, pressure, check to make sure your compressor clutch is engaging.

[jamesblonde82]

does the compressor still kick on when you turn on the a/c? it's very easy to add more freon if you have the equipment. i have the equipment but i didn't know how much was suppose to go in so i just took it to a guy i know with a shop and he put it in for me. also there is a little window in part of the system thats located right of the battery somewhere by the radiator kinda, and if the window is milky when the system is on that means it's low and needs more. if its not milky looking and its on, then theres something else wrong. hope this helps.

[94_240sx]

I've never serviced my A/C since I got it, but it's still blowing really cold. I'm talking about no A/C service for about 9 years. I think mine is factory installed A/C.

[cmkelly]

I've never had to service the AC of any car I've owned so this is new to me. I'm pretty sure it's gonna be R-12 versus R-134. You used to be able to get R-12 at any auto parts store but that was a while ago. I know there's also usually a glass bubble gauge that shows if freon is present or low which I'll check tonight. I drove the Pathfinder today because it's HOT!

[jamesblonde82]

you can get the replacement for r12 called freeze 12 at NAPA. (used to work there) when i serviced my a/c it was on my 92' and it was blowing cold still but the glass was milky so it was a little low, so i just added more. the 93' supposedly has a new compressor and is real real cold. perfect because its 100 degrees today and i don't wanna drive with the top down and get my scalp burnt again, yes i have hair.

[waitn4sno]

search FSM factory service manual.

HA (heating & AC system) file is very informative.

Good luck

[ishkabibble]

It's an R-12 system. Normal R-12 is very expensive these days, but you can still get a recharge with it at a few places.

Your other options are Freeze 12 (which requires an evacuation of the system), or an R134a conversion.

I researched this a couple of weeks ago and decided that it is not one of the things I would DIY.

[cmkelly]

Just an update; it turns out that my A/C is fine. The water pump problem I was having caused the AC/ not to work effectively. Once I had the water pump replaced the A/C has worked fine.

Since then I heard a local commercial for a radiator shop and one of the signs of a coolant problem is ineffective A/C.

Hope this helps someone else.

[biggie]

That is true, if the AC suddenly stops blowing cold air, overheating could be the issue.

Noticed that a couple weeks ago, when my thermo was sticking.

[ishkabibble]

Well, lucky me, my a/c compressor seized on Sunday and it's insanely hot this week. I'm debating if I should just rebuild the entire a/c system with new parts (About $600-$700), or replace the compressor with an used compressor and then get the system flushed and recharged with Freeze 12 (under $200).

I might be buying another car in the next couple of weeks, so I guess the decision hinges on that. Meanwhile, I'm going to be sweating it out.

[RunCool]

If you guys are doing any work on your A/C system your best bet is to convert it over to R-134. Its very easy to do. First off your going to need your old R12 vacuumed out. Once that it is done, it is recommended to change the receiver dryer, because it has the old R12 oil in it, which should not be mixed with the new pag oil but you can mix it and it won't harm your system really. Then remove the stems from the old R12 high and low side. Install R134 fitting, and charge it from the low side with the AC on high. Buy a can that has the pag oil mixed in it, use about 6 ounces. Start with two cans of R134 (1can of stop lead won't hurt), and check the low side pressure with one of the gauges you get when you buy the can. Its not the most accurate thing but it works. Should be around 28 if i remember.

[biggie]

If you guys are doing any work on your A/C system your best bet is to convert it over to R-134. Its very easy to do. First off your going to need your old R12 vacuumed out. Once that it is done, it is recommended to change the receiver dryer, because it has the old R12 oil in it, which should not be mixed with the new pag oil but you can mix it and it won't harm your system really. Then remove the stems from the old R12 high and low side. Install R134 fitting, and charge it from the low side with the AC on high. Buy a can that has the pag oil mixed in it, use about 6 ounces. Start with two cans of R134 (1can of stop lead won't hurt), and check the low side pressure with one of the gauges you get when you buy the can. Its not the most accurate thing but it works. Should be around 28 if i remember.

This should only apply to '92s on here. '93+ were R134 from factory.

[jamesblonde82]

not sure, but i think my 93' is R-12. stuff looks the same as my 92' did. how can i tell?

[biggie]

not sure, but i think my 93' is R-12. stuff looks the same as my 92' did. how can i tell?

From what I've been told they look the same. When I was messing with my '92 I was told by some Nissan mechs that the '93s were R134 from the factory. Guess it could be wrong, could be based on production date instead of model year too.

[ishkabibble]

It's based on production date. Nissan switched to R134a partway through 1993. The month probably varies on different models - I have no idea when verts changed over.

The a/c fittings should be different between R12 and R134a. Also, I think R12 uses black caps on the fitting and R134a uses blue and red caps. Don't quote me on these things, though; I've only researched this stuff but haven't actually worked on it yet.

[drewc87]

fourseasons makes a retro fit kit to convert the system to 134a. the part number is 26245 and comes with a high and low side adaptor, the bottle of oil, caps for the fittings , and misc seals. or you can just change the fittings. fourseasons part numbers 59976 low side, then on the high side its either 59977 for 1/4" or 59978 for 3/16". i do not know what size the high side is but one of those part numbers will work. also remember if you open the system to replace the drier and the orifice tube/expansion valve. i think your best bet is to just use freeze 12. its going to be the cheapest way.

[NaXu]

not sure, but i think my 93' is R-12. stuff looks the same as my 92' did. how can i tell?

You've probably done it already, but in case not... Have you checked the label under the hood? It should say which refrigerant the system has (and it also has other info about the a/c system)...

(Btw, my Vert is ´93 and has R12. Now about to change it to R413a because R12 is not available here anymore.)

[woots]

You can get r12 on ebay.....R12 systems seem to cool much better with r12 than with a 134 conversion. BTW cars thru 93' were r12 and 94's were r134. i've had both and i now drive the 94'. Nice and cool here in Florida

Woots

[jamesblonde82]

what do the little tips looks like on the r134? i think my 93' is R134 cuz my 92's tips looks different.