Automotive Air Conditioning Information Forum (Archives)

98audiA4 on Sat July 17, 2010 10:04 PM

Year: 1991
Make: dodge
Model: spirit r/t
Engine Size: 2.2
Refrigerant Type: r134a
Ambient Temp: 87
Pressure Low: 5
Pressure High: 220

see below for more accurate system info

Edited: Sun July 18, 2010 at 8:39 PM by 98audiA4

98audiA4 on Sun July 18, 2010 5:48 PM

ok....

well, lots of googling told me that I had air in the system. I also visited the junkyard today after measing the area where my condenser goes. either the PO was wrong or the rerouting of some intercooler lines freed up space but I found that a Parallel flow condenser from a 95 spirit fit just fine. I also nabbed the expansion valve. Both were in great shape and I cut the lines going to the condenser so I could test for leaks.

I got the condenser home and hooked up a small regulator and put 120 psi of air in it and dunked it in a small kiddie pool I use for my dogs. After 30 minutes in there with not a hint of a leak I took it out and blew all the remaining oil out of it. It came out clean albeit a little caramel color. I put several ounces of lacquer thinner in it and turned it all varieties of ways to work it all around inside and then hung it upside down to drain for a while. Once that was over, using the regulator, I ran air through it for quite a while. Put it all back together and its been sitting in 29" of vac for a while now.


So here's my question. What's the R-134a capacity of a 1995 Dodge spirit? I'm going at this system as if it were 134a from the get-go. I have a completely clean (or reasonably clean anyway) system with 7oz Ester oil, a parallel flow condenser, a r-134a TXV and a new drier.ft>


thanks

bohica2xo on Sun July 18, 2010 6:37 PM

Never seen one of those with anything but an A590 compressor. The scroll sounds like an aftermarket decision by an owner.

Your first posts indicate a condensor issue. The high pressures were way out of line. The low side could have been a TXV issue. Now that all of that has changed it is hard to say what you will see.

My chart says 26 ounces of 134a for all engines in a 1994 Spirit.

B.

-------------------------
"Among the many misdeeds of the British rule in India, history will look upon the act of depriving a whole nation of arms, as the blackest."
~ Mahatma Gandhi, Gandhi, An Autobiography, M. K. Gandhi, page 446.

98audiA4 on Sun July 18, 2010 6:55 PM

ok, thanks. I added 30 (my snap-on act-4100 manual says the hoses hold ~4 ounces).
At 2000 rpm sitting still with a light mist of the hose here's what I got:
230 high
~12 low (when the compressor kicks on it hits about 5 and works its way up to around 12-15)
90 ambient
48 vent temp

I assure you it is not an aftermarket compressor. Its a Sanden TRF-105 only found on the 1991&1992 Dodge Spirit R/T 2.2 Turbo III. (91-93 Daytona Iroc R/T)
I think they also used the TRF on some mid-late 90's full size vans but it had different ports or clutch or mounting holes.

The vent temp I feel is pretty good considering the 90 ambient however the low side being so low still seems odd. This is with a completely different condenser and a completely different TXV (different part number). The TXV I removed showed it was from a 91 caravan the one I put on showed it was from a 94-95 acclaim (spirit) which makes perfect sense since that's what it came off of.

Any reason I should continue to tinker with this or does it sound fine? Maybe the machine's low side sensor is acting up? I'm charging with a dinky parts store hose still since I can't justify 200 dollars or so on a full 30 pounds. I purge the line upside every time i connect it. The charging hose claims the pressure is around 40-50.

IF I believe the charging hose low pressure it LOOKS like everything is right. IF I believe the machine's low side reading things still look funky.

Edited: Sun July 18, 2010 at 6:57 PM by 98audiA4

bohica2xo on Sun July 18, 2010 8:09 PM

Put the gauges on it & go for a drive.

Unless you drive with a garden hose on the condensor, you are fooling yourself.

As long as the high side stays below 275 @ 95f & 2000 engine parked with the doors open & cabin fan on high you should be ok.

B.

-------------------------
"Among the many misdeeds of the British rule in India, history will look upon the act of depriving a whole nation of arms, as the blackest."
~ Mahatma Gandhi, Gandhi, An Autobiography, M. K. Gandhi, page 446.

98audiA4 on Sun July 18, 2010 8:38 PM

the garden hose is because i know the fan is slightly inadequate, it's more to simulate the car in motion (25-35mph, 2000rpm). By mist i mean: I set the hose on the bumper cover, crack the valve (I have a valve on the end of the hose that I can shut off for adding or removing attachments) ever so slighly, and aim it at the center of the condenser. The top half of the condenser doesn't get any of the spray, it's very directed at the center and of course it trickles down a bit. It's a very fine, small mist to supplement the fan.


I don't have a way to read pressure while driving unfortunately. A nice set of gauges is on the wishlist, though. I'm done with it for the night so the driving test will have to wait.
thanks for the help, I do appreciate it.

Edited: Sun July 18, 2010 at 8:44 PM by 98audiA4

98audiA4 on Mon July 19, 2010 7:24 AM

For those with any interest still I took some temp readings when i got to work (where i have a small IR thermometer) and this is what I've got:
72 ambient
internet says 99% humidity, plenty of SWEAT on the suction line between evap and comp

Inlet/outlet drier: 91/95
comp outlet: 120+
suction at comp:40 something
evap in/out 90 something/ ~34
vent temp: 30 and I have an analog instant read inserted in there and it says 45, starting to wonder which one of these things is right

looks pretty good

if the evap was blocked with leaves/dust/pine needles would that contribute to low suction pressure? The car IS 20 years old with no cabin filter.

Edited: Mon July 19, 2010 at 7:53 AM by 98audiA4

98audiA4 on Tue July 20, 2010 7:37 AM

I took off the blower cover and the evaporator is nice and clean, just a few leaves in a lower corner. While I was there I jumped the evaporator thermostat and was able to achieve lower vent temps (the high and low switches never cut out the system) into the high 30s according to my analog instant read. The evaporator was not frosting over so that's also good. I put a switch in-line temporarily and with it off it seems to regulate the vent temps to right at 50. Flip the switch, wait 2-3 minutes...38 degrees.

Do you guys sell adjustable evaporator 3 wire cut-off thermostatic switches?

Edited: Tue July 20, 2010 at 7:39 AM by 98audiA4

98audiA4 on Tue August 03, 2010 8:21 AM

you're probably all tired of hearing from me.

i found in a 94 spirit a Modine condenser (with chrysler OEM label and part #s) with the large round tube on the ends and the flat channels that run end to end. it visually resembles the condensers i see on modern vehicles and has a compatible flange for my lines. it is externally very, very clean and the car it came off of was very clean with low miles. i guess it had a failed water pump which killed the engine, too bad too.

i'm pretty excited to have finally found the best condenser out there for the car. i'm about 6 ounces short of the full charge (ran out) and already cooling is great. after work today i'll get the rest in there and see how my pressures are.
with the low charge (20 ounces) the high was about 130psi with 80f ambient and 48f degree vent temps. the evaporator switch is still shutting the system off right around 50f vent temps. without replacing it i feel i'll forever be at 50 degree vent temps. so far the high side pressure looks way, way better than when i started this whole thing (~300, albeit the ambient temperature was higher).

bohica2xo on Tue August 03, 2010 1:52 PM

Um, is that what you consider a "clean" condensor?

B.


-------------------------
"Among the many misdeeds of the British rule in India, history will look upon the act of depriving a whole nation of arms, as the blackest."
~ Mahatma Gandhi, Gandhi, An Autobiography, M. K. Gandhi, page 446.

98audiA4 on Wed August 04, 2010 8:00 AM

clean, as in no huge damp-looking oily spots in the corners, no bent fins, no dents or dings or rock hits. for being 16 years old in NE ohio in the rust belt (i know, its aluminum) where the weather and the area is hard on every vehicle the condition of the condenser looks "clean." it still needs all the accumulated dirt and crap off of it but its a good start. i've heard simple green does a good job of eating all that crap away and i intend on cleaning the outside this week when i have a chance. guess i should have used a different word to describe it