DaveK

I saw something on a website somewhere (can't remember where) that basically said the part would work with R12 and R134. I get the impression the only difference is that the R134 ones don't have a sight glass since it's not so useful, but that doesn't mean that one with a sight glass isn't R134 compatible.

DaveK

Thanks to Springer3's description of the receiver / dryer operation, I've figured out a way to test whether I've got the wrong part or the right part with the wrong flow label. If the whole point of the receiver part is to separate the liquid and gas - and to do this it has one short input pipe (which ends at the top) and one long output pipe (which ends at the bottom) then :

If I suck (or blow) through one connector - then the other one will make a noise as the air enters / exits. The longer the pipe - the deeper the tone - so if I blow through the short input pipe, the air exits the output pipe and sounds fairly deep. If I blow through the long output pipe, the air exits the short input pipe and sounds higher.

Obviously not ideal, since I'm sure I'm introducing vapour - however, I don't believe a brief "suck in" will kill the dessicant - after all, it's open to atmosphere for a few minutes while I connect the pipes anyway. Just won't do it on a damp day.

I tried this experiment on the old dryer I'd taken off - and it worked exactly as expected. So once my new keys turn up and I can get to the new part, I'll take it off (fortunately, I have spare o-rings) and try it out. I can then confirm whether I have the correct part or the wrong part.

Thanks to Springer3 for the description - wouldn't have thought this up without it.

springer3

I have not heard of any design changes in the receiver/dryer for R-12 versus R134a operation. I believe they are still interchangeable.

Daves "organ pipe" experiment should work, and I'll bet you will find the installed direction correct. I think you can minimize the moisture absorbed by first heating the receiver/dryer with a hair dryer or a work lamp. If you raise its temperature 10 degrees above your body temperature, that will effectively lower the relative humidity of what you introduce into the dryer. I would get the system on the vacuum pump asap just to make sure the dessicant does not have time to adsorb the moisture.

Good luck!

jeff4510

Hi there, I am getting a leak in my ac from the same area that lets the water drip out from the normal condensation (use of the ac). I guess I have a bad heat transfer? The little radiator that lets the cool air pass over it before it comes into the cabin? Is there any other ac component in that general area? Any diagrams available online so the AC guy can have a reference? It's converted to r134. thanks! Jeff 89c4

DaveK

Well, I checked and...... I have the right part, wrong flow sticker on it. Funnily enough - the difference in tone isn't as pronounced as it is on the part I took off - which suggests the 4-seasons one has a slightly longer input pipe (or maybe wider). But at least I now know I have the right part.

Will try and get it recharged this afternoon and we'll see if I still have a leak.

jeff4510

ok, so my leak only happens (at least visibly, the die) when using the ac. So my questions are: Access to the heat exchange is from the trunk or from in the cabin? Is there anything else in that vicinity that could be leaking (valve etc)? thanks!

DaveK

OK - from your description, I guess you mean the evaporator. From the diagrams I've seen, there isn't anything else in that area - although the expansion valve is also there (but it's higher up). To replace the evaporator is a lot of labour - I've been told by my mechanic that the fuel tank has to come out (although I was told on this board it can be done without that). I believe that part of the dash also has to come out - if you search for evaporator you should find posts on it, because I asked a question about it a few months ago.

gfunk

For reference here is a diagram of the heater/air conditioner assy. The evaporator and expansion valve are pretty well buried.

jeff4510

thanks a bunch, weird that the evaporator would be bad. I bet its something simpler, like that valve. Is the evaporater and the valve on the trunk side of the firewall?