khmerspec

ive got an 87 rx7 gxl

it has been sitting around for about 2 years, but has only 50xxx miles on it.

ac dosen't blow cold, but it blows.

is there anyway to revive it?

satch

iTrader: (1)

If the compressor is in good shape and the system doesn't have leaks and you replace the drier and recharge it with freon you should be good to go but those are a lot of variables to deal with

2ndgencab

Convert it to R134 and give it a shot.Atleast you will know where you stand with it. GL

khmerspec

I'm still new to all the DIY stuff, so how do I tell if the compressor is good?

also how would i convert to R134

gxl90rx7

iTrader: (1)

yes, i went revived the a/c in my 10AE last summer, still works today. all i did is replace a few o-rings and recharge with R134. I didnt pull vacuum before i charged it, but it is still cold, just not as good as it could be. i plan to vacuum and recharge it next summer

all you need is an a/c o-ring kit, a couple of r134 cans, an r134 oil can, r134 to R12 adapter fittings, a vacuum pump (you could get a shop to do this, then drive it home), and an a/c pressure gauge kit with charging hoses. Basically just replace all the o-rings (most likely the cause of your a/c problems), hook up vacuum pump to about 25-30 inHg, then charge it with the r134 oil and refrigerant. charge it up to about 30-35 psi on the low side with the engine running and a/c full blast


actually before you do all that, you could just charge your system with a can of r134 and see if it holds the charge. your compressor should come on once you have enough pressure in the system. if not, start tracing the problem.. it could be a bad pressure switch, or bad wiring to your logicon. if the compressor still doesnt come on, check the wire for 12V. if its got 12V, and it isnt on, then its a bad compressor. I ended up having to rewire mine with a jumper, cause the stock a/c switch runs through your ECU, and i am running haltech

jackhild59

iTrader: (7)

You should not charge with 134a unless you live in an area where A/C is really not necessary, because you will get poor results. FC's are poor candidates for R134a due to inadequate condenser capacity. This is well documented on this site. If you charge with R134a, you will either have excessive high-side pressures or you will have greatly reduced capacity or both. Everything that a beginner in A/C does wrong makes the results worse. If you MUST use R134a, you should replace the condenser with a parallel flow condenser to increase capacity. This is a custom job requiring professional A/C and fabrication skills.

If you try a professional A/C shop, they will tell you that they can convert you to R134a with no problems. Later, when you take your car back to complain, they will basically say 'That's as good as it gets.'

Other Bad Ideas include any of the fuel based refrigerants.

Best way to fix our A/C is with the original R12. I do this all the time. FC A/C is great with R12. I am the leading guru and proponent of R12 on this board.

Next best is Freeze12. You can get a very nice A/C with little downside using Freeze12. Many FC owners in Arizona are happy satisfied Freeze12 users. If I couldn't get R12, I would be very happy with Freeze12.

Good Luck.

lonewolfrx

r12 blows alot colder than the 134. But the only reason i switched to 134 is because the local stores wouldnt sell it to me. After vacuuming the system and recharging it it blew cold but not as cold.

Oh and to check ac you can push the stem down on the ac port and see if pressure come out to see if theres freon. If theres not there might be a leak. Vacuum it and see if the vacuum on the guage goes back to 0.

Spin the clutch on the compressor it self to see if its not seize up. If your pipes disconnected off the compressor spin the clutch hand listen to where the hole for the lines are. Try to cover the holes with your fingers while doing this. Should feel pressure building up on one and vacuum on the other. If theres nothing it might need oil or its shot.

Thats just what i know. You can try that to check your system.

jackhild59

iTrader: (7)

It's not just that R12 is colder, It's that the system will have greater capacity to move heat when using R12 or Freeze 12. Stated another way, the system loses capacity to move heat when you use R134a. Not because there is anything wrong with 134a, it's just that our condenser is not correctly sized for 134a.

Yes, you must have a license to purchase R12, but you can buy Freeze 12 on ebay and local parts stores without a license. Next time give Freeze 12 a try. It really does work well. Your 134a system will not perform very well when it is hot outside, or in traffic, or when the interior is heat-soaked etc. I'm glad you have it working, just know you *can* have it better with the freeze12.

j9fd3s

iTrader: (3)

true! local car here actually had a hose explode.

couple of my other friends have gone to R134 without any trouble, except its just not as cold

khmerspec

Thanks guys.

Lots of good info, I had gotten a can of r134 but it didn't work (forgot i needed a convertkit), and cant return it.

but ill try out r12.

lonewolfrx

id get a pressure guage while you at it. you can monitor the low and high side pressure. make sure the the pressure isnt too low or too high if it kicks in, especially the high side. maybe invest in a condenser fan as well to help keep the pressure down a bit.

2ndgencab

Never heard of Freeze12. Can you get it in the great state of Ca? lol

Mutaku

I've used freeze12 with good results and yes you can get it in CA. I would make sure that you replace the dryer and check for leaks before you do it just to save you some money in the long run. It'll blow colder and wont have to be recharged as often. If you have to replace something major like the compressor I'd look into possibly doing a proper r134 retrofit. Though it may be simpler to just replace, flush, check for leaks and fill with r12 or freeze12 if you are unable to obtain r12.

jackhild59

iTrader: (7)

Freeze12 is partly 134a and the retro fit kits contain ester oil.

Good refrigeration practice dictates that you should replace the dryer if the system has been open or depressurized for any length of time. However if your receiver dryer has never been replaced be aware that the fabric internal bag that retains the desiccant can *dissolve* when you add ester oil and R134a. It was never designed or intended to be resistant to the modern synthetic oils like Ester and PAG. The dessicant will escape into the system and clog up everything. This is a Bad Thing.

Since about 1996 all the replacement dryers are manufactured for R134a and the synthetic oils. They work fine for R12 and mineral oils as well.

This also dictates that if you find a 'new old stock' dryer, don't use it. Get one rated for R134a.