since I've got my back wheel off for my cooling system leaking problem, thought I'd address my a/c as well. The a/c works in that it's alittle cooler than the outside temperature, but not nearly as cool as my other cars. My surburban shows around 47 degrees as the a/c vent. The ferrari is 59. I tried putting in some freon (I have an R12 system, and I put in some freeze 12 which is legal and compatible with both 12 and 134a, oil wise). That didn't help much. I don't have sophisticated gages, only a tire pressure type a/c gage. Might try putting some more freon in, if it still reads low. but the basic question is aside from the lousy air distribution (I just have the three top vents, not the waist vent); can an old ferrari with the original compressor do better than 59 at the vent? if so what's the step after making sure the freon's topped off. saw all the discussion about replacing tyhe compressor and the rest, but it seems to me that my system should be able to go down to around 47 degrees if only I did. . . ? that's what I'm looking for. thanks
Mine will blow 47, in fact I have seen it creep near 40 on a cool evening. You need to really vacuum it down well, swap the dryer and refill before you right it off. To keep it blowing as cold as possible try to stay with the R12. I know there are better compressors out there but they will require the switch to 134 and it just doesn't seem to get as cold.
Be care on how much you put in. You may blow seals. You need gauges for this job. Correct amount should be weighed in. If system was flat before you added gas you need to evacuate and start over.
Dr Tommy, ricjaffe has a system that's holding R12 coolant, he's just trying to top it off, so doesn't need a new dryer, etc. What he does need is a good set of R12 A/C gauges, & instructions on using them. (Often go for $25-$35 on eBAY, not much demand for R12 gauges any more. Most people don't realize that you can use the gauges with any refrigerant, you just need the correct temp-pressure tables & can't use the refrigerant specific calibrations on the gauge dial.) ricjaffe, While freeze12 is R12 compatible, it's temp-pressure curve is just different enough so that the gauge readings for the R12-FREEZE12 mixture are going to be slightly off from either refrigerant's temp-pressure curve. You're going to have to use the R12 readings to get you into the ballpark, & slightly undercharged. Then fine tune your cooling by slowly adding coolant until your system gets to a low temp, then rises slightly. Since you just added FREEZE12, w/o gauges it's possible you have over-charged the system & will have to remove some to get the pressures & temp. down. I recommend you go to the library & check out a book on auto A/C service, or buy a book. You need to do some studying. MIXING REFRIGERANTS HAS A DOWN-SIDE: You're not going to like hearing this, but you're now likely to be on your own A/C service wise. If you ever take your car to an A/C service shop, you MUST tell them the system has a mix of R12 & FREEZE12 before they hook their equipment up to your car. Unfortunately, most shops won't/can't service a mixed coolant system because by their equipment recovers the coolant for recycling. The recovery equipment, and even the larger recyclers cannot separate blended refrigerants. The shops know that they can't trust their gauge readings if their system has been "contaminated" by another refrigerant, even one closely similar. Also, if a recycler finds that a shop has sold him "contaminated" refrigerant for recycling, the recycler may stop accepting from that shop. A shop can't even legally drain your system into the air & pump it down. There's a big EPA fine for venting refrigerant into the air if they get caught. Sorry about the lecture, Just felt you needed to know where you stand for future reference.
I'm to the point that I am taking out my old compressor, any tips on the removal? There seems to be a coolant pipe in the way and I think I have take off the alternator belt and A/C belt. What do you guys think? Can I take it out without removing the coolant pipe? Am I on the right track? Should I take it out through the side wheel well or up top? What would be easier? Thanks! Dom
AC on the 85 308GTS blows at about 40F. Last year i took it to a local truck repair facility and we evacuated the old stuff twice as i did not know the condition and repeated evacuation was suggested by others here. We did a pressure test and it was fine. This tests the seals. We then evacuated a third time and refilled with R12. Result: Blows DAMN cold that even my gal, who loves AC and is the only reason i kept the AC system in the car verses removing it to lower weight, says the AC is colder than any car (mainly Beemers) she has ever known. Must admit, it blows VERY cold and last week we used it and had to keep the fan setting on low and allow the thermostat to do its magic.
Rickjaffe, I'm posting the response here as it's related to your earlier question in this thread. More likely you're either under or over charged & one of the pressure limit switches is turning the compressor off because the high side pressure was too high, or low side pressure was too low. You really need a set of gauges to diagnose this kind of a problem. If high side pressure is too high, adding coolant can cause something to literally explode. BTW, Pls don't start a 2nd thread when you already have a thread on the same general subject going.
took the car to my mechanic. the pressures are of initially ok, for 10 minutes maybe, but then they get very high: 68 low and over 300 high. and after 10 minutes the a/c blows progressively less cool air up to the point when it blows ambient air; he's recommending I get an new expansion valve. If so I'll also pop for a new dryer, and change to 134a. He doesn't think the compressor needs to be changed since it's working and holding plenty of pressure. I remember reading somewhere that a bmw dryer can be used in a 308 (GT4) what specific type of dryer is it, if anyone knows?
The over pressure switch is shutting things down. Your mechanic's diagnosis sounds right, something's clogging up the system. He's probably already planning to do it, but you might check to see if he's going to flush the system while it's apart. Usually what cloggs up a/c systems is the dryer's dessicant powder bag leaking dessicant powder into the system. All of the powder needs to be removed to ensure it won't circulate around & clog things up again. As for dryer exchanges, Search the body of posts in both the current & old ferrarichat archives for: 'dryer' and 'air conditioner' There are 3 or 4 different dryer exchanges that have been used successfully. Several of the threads have pictures as well. The dryer will have to be rated for R134a as the older R12 dessicant is not completely R134a compatible. Most new dryers use a dessicant that's safe for either refrigerant. Might want to do an search for 'expansion valve' as well. Again several exchange parts have been successfully used. However, your mechanic should be able to take the old one dryer & expansion falve & cross-reference both of them.
took the car from the shop to steve carr's place. he noticed that the goopy tape was on the expansion valve, but not on the sensor; he thought that could be causing the problem. nice catch on his part; it helped alittle, but still didn't work too well. got a BMW dryer from him (39 bucks( just have to cut off some wing things on it. also got an expansion valve. (29 bucks) he happened to see that I had freeze 12 in the back seat; he highlyrecommended that I use that instead of 134a; says it's 80% 134a and 20% something else (144?); says it works better than 134a; could use ten percent more than 134a (and 10% less than 12a); took his advice and will use that (don't need to change the fittings with freeze 12. Carr is a very good, guy. extremely knowledgable; he's the guy who helped sean F fix up his sanden conversion in his 308. I highly recommend him as a resource and for parts. will give an update in a day or so when I get the car back. thanks.
Rick, Glad Steve was able to help you out. He was a big help to me in getting my rotary compressor put on and my system up and running. It blew 44° on a 90° day in Houston last fall sitting in his parking lot. The biggest problem with the system IMO is that it does not distribute the air very well. It all comes out the middle. One side of you is cold and the other is burning hot in the sun!
Man I drool reading your post. I have an 88 535I with only 67K orig mi on it and that has the very best AC system I have ever known, even AC Delco systems. Your GTS system rocks. My GT4 system stinks, barely keeps the cockpit comfortable on a warm day, but is better than nothing. I probably need to have mine evacuated again. Mine also seems to not cool down as much after it has been running for over 30 minutes. Sounds like an expansion valve for me also.
Rember that the vent temps are also a function of the outside temperature, so comparing them needs to be done carefully. You really need to know the outside temp & airflow thru the condensor before you can compare them. An A/C system in 75 degree weather will blow 15 or so degrees colder than that same system in 95 degree weather. Simliarly, testing the same car in 85 degree air will be 5 to 10 degrees different if one test has a big fan blowing air into the grille.
well I got the car back to test out the a/c. I put in a new BMW dryer, new expansion value; some other thing was causing the system not to hold pressue (some kind of sensor, I forget; replaced that as well); the system was flushed, no blockages; 3 cans of freeze 12 were put in the sytem. pressues were good: 40 low 250 high. The only problem is that it doesn't blow cold. tonight I got down to about 66-68 on a warm, humid houston night (may be low 80's or so). during the test at six or so with outside air over 90, it was alittle better than ambient but not much. I tried various adjustments with the heater control value (the middle switch between the air vents) and that didn't seem to do much; I located what that switch in the front of the car. it didn't move much, but then I guess what moves is inside the hose, a value to block off the hot water to something or other. that led me to a thought and a past experience; I had an after market a/c system put in my C-2 vette; (sanden compressor, 134a) initially it wouldn't blow cold. Turns out the switch which came with the kit to do the same thing (stop the hot water from entering the system) wasn't completly blocking the hot water. The guy had to install a special value, which I manually close on the hose to shut off the hot water. I just do it once a year and the a/c worked after that. Is it possible I'm having the same problem here; namely that the hot water cut off switch isn't keeping all the water out. the value looks old and has some crud on wir. but of course the mechanism is inside the hose I think, and I guess there's no way to tell whether it's working; (but as I said previously, there didn't seem to be a big difference between the position full down (red or open I presume) and full up (blue, closed); maybe that's a tell-tale sign that it's not completely functioning. for the sake of argument and to test this hypothesis; what would happen if I unhooked that line and plugged it up? is there another way to test this or make sure that the valve is completely closing and no hot water is entering the system. it's not like I'm getting hot air in the air vents and cold air through the a/c vents. the a/c vents just don't blow cold. So I guess I want to confirm that that hot water switch can affect the temperature blowing through the a/c vents. is it worth getting some kind of new manual valve from pep boys, disconnecting the one connected to the switch and trying that? any other ideas? thanks.
I had a 78 308 years ago and the only thing that worked exceptionatly well was the AC. It worked better than my wifes new Bmw of the time. You could hang meat in that car.
this morning, the a/c went to around the mid 50's then after about 15 minutes went to 60 or so, OAT was in upper 70's or low 80's and typical humid houston morning. Looks like I've still got both problems; not getting cool enough and, it's only cooling initially. now that I know the system holds a vaccum, there's no air in the system and I've got a new expansion value and dryer, and there are no restrictions in the line, the only thing I can think of is the hot water issue. Am I missing something?
I have heard some stories about 3X8 A/Cs keeping the car cool, but I've heard a lot more about how ineffective they are. In my 328, the air coming out of the ducts can be cool 45 Deg, and I have the heater hoses blocked-off (the last thing needed in a 3X8, in So Ca. is heat) but there really isn't much air volume. A modern car has significantly more ducts, fan power, and a lot less windshield angel the 3X8's. The 328 has a common York compressor which could probably produce a ton of cooling capacity, but it seems to me the 3X8 blowers are a weak link. To me, it is no wonder that the 3X8 A/C units are marginally effective. Just compare the size of the blower motors in a modern car Vs the 3X8--a modern car blower motor draws 10+ amps. Have not measured the cute little motor in the 328, but it is probably in the vicinity of 3 amps. A modern blower fan is about 6inchs in Dia, whereas the 328 seems to be less than 2. I have entertained putting a bigger motor in from a BMW 2002--they seem to have a similar set-up. Also, in the 328, the only dash duct that gets chilled air is the center one; the others only work for heat. The console ducts also provide cool air, but there is a lot more capacity for hot air. I hope you find something, please keep us posted on your journey. Mark
here's a picture of the valve and hose which I think is controlled by the middle switch in the car I'm planning on seeing if I can get a cut-off value and put it between the hose the car's valve, on the theory that perhaps the valve is corroded, inoperative, or otherwise doesn't fully close. anyone see any problems with trying this? Image Unavailable, Please Login
just an update; I've got all this new stuff (dryer, expansion valve, and some other valve which was leaking) 3 cans of freeze 12. adjusted left air vent. still no go. thought about by-passing the heater, but my mechanic/ac guy, once he looked over the system, said it probably wouldn't help. the system appears to be operating ie it's "sweating". the compressor seems to be operating fine (pressue is good); he said the sanden might help at idle but the extra 4 pistons wouldn't make any difference after 1500 rpm with some air flow; I'm getting about 80 degress off the vent on a 95 degree day. seems kind of warm; one thing I was wondering; does this system have a recirculating air system, rather than fresh air? would that be vent levers up? I've heard that these old ferrari system don't work too well, but this seems ridiculous. I get really cold air in my after market sanden with 134a in my vette. I'm not even talking the poor airflow design, just raw temp. this can't be the way it was designed.
My compressor has suddenly decided to stop working. No signal at all to the compressor. I put a multi-meter from the electrical lead to ground and I get no voltage at all. It's like the LP cut off switch won't come on. If it was the exp. valve I have the same problem you do, cold air at first then nothing. Or the compressor should at least cycle on/off. The system has pressure and no leaks. It was blowing cold last weekend, now warm air. Check you center controls. Is the cool/heat (that little knob b/w the seats with the red/blue) all the way on blue? If so, double check the cable itself is doing what it's supposed to. Once, I had my system on and could not figure out why it was blowing warm when I realized the lever was in the hot position and was mixing hot air with the cold.
FWIW: With the AC themostats getting hard to find at F-dealers for 328s, I was checking the application notes for the GE Industrial original part (3ART5). According to the app notes, you should avoid mounting the sensor capillary tube in a tip-high vertical position, because gravity feed with interfere with the thermal sensor operation. And how is that capillary tube mounted in a 328 (and 308?)? -- Ayup. I guess I'm gonna have to find time to finish my thermistor/op-amp electronic themostat project.
you would think there should be a difference between keeping the lever in the blue position (hot water on) and red (no hot water), but on my car moving the lever between the two position doesn't change the duct temperature. so I'm thinking the lever/valve doesn't work at all. I bought a 3/4" heater bypass pipe and I'm going to try to by pass the heater once the car cools down. keep us posted on your compressor. could the sanden just crapped out?
