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  • donalson

    June 25, 2009 1:20 p.m. donalson UltraDork

    I don't know much about a/c systems... they're one of those things I've not bothered fixing in the past... but it's hot enough and the a/c in the car is just enough of a tease for me to want to fix it...

    '91 ford escort... a/c blows cool but not cold... sometimes takes a while for it to kick in... sometimes it's cooler then others... figured it just needed some coolant added... no biggie i've got a spare hose and can I bought from last year and due to car changes never used...

    went out to the car, shook the can, started car with a/c on max, hooked up the hose (with pressure gauge on it) (looks like this one) to check where I stood...

    gauge was going from right between the green/blue to dabbing into the red, then it would go back down... I could hear a relay kicking on and off...

    whats the deal?... thanks guys mark

  • John Brown

    June 25, 2009 2:05 p.m. John Brown MegaDork

    BTW that car is an R12 system running R134a.

  • Strizzo

    June 25, 2009 2:07 p.m. Strizzo Dork

    that is normal with the cycling of the compressor on and off. not sure what could be causing it to be warmer some days though. is the heater blend vacuum operated? i had a vac hard line crack and would only hold the heater door closed under light cruise or idle, when pulling away from a stop the heat would come on full blast through the defrosters. not fun on a 98 degree texas day.

  • Tom_Spangler

    June 25, 2009 2:13 p.m. Tom_Spangler New Reader

    John Brown wrote:

    BTW that car is an R12 system running R134a.

    I had an 89 Mustang that had been converted, and the AC was always "good but not great". If the car was moving above, say 40mph, the AC was adequate. Below that speed, you might as well open the windows.

  • slefain

    June 25, 2009 2:17 p.m. slefain Dork

    When I convert R12 systesm to R134a I like to let the vacuum pump run on it for a good hour. Then I can dump my R134a in it. You can also do what I did on my old Lincoln. I added an electric fan to the condenser that switched on through a relay hooked through the A/C clutch relay. Clutch kicks on, electric fan kicks on. Kept the A/C cool.

    Find someone with a vacuum pump and a set of gauges. Vac the system down and then refill it. I bet it will make ice cubes after that.

  • friedgreencorrado

    June 25, 2009 2:29 p.m. friedgreencorrado HalfDork

    Tom_Spangler wrote:

    John Brown wrote:

    BTW that car is an R12 system running R134a.

    I had an 89 Mustang that had been converted, and the AC was always "good but not great". If the car was moving above, say 40mph, the AC was adequate. Below that speed, you might as well open the windows.

    My `92 VW 8v GTI is doing that right now. I wonder if it's related to the new noise in the compressor..

    It blows cold when the engine's over 2K rpm. I'm using my heel-and-toe skills to keep cool at long stoplights.

  • donalson

    June 25, 2009 2:59 p.m. donalson UltraDork

    thanks guys... father in-law has the vac and gauges i'll have him look at it I suppose :)

    the one bad part of FL is the summer heat doh...

  • cwh

    June 25, 2009 3:03 p.m. cwh Dork

    SoFla had 100* day before yesterday, and my truck AC crapped out. Drip, drip.

  • friedgreencorrado

    June 25, 2009 3:49 p.m. friedgreencorrado HalfDork

    Yeah, we're not far behind you here in GA. Been flirting with 95 for a week and a half. And I recently got diagnosed with high blood pressure-the docs say high heat makes it worse. I've converted two of mine to R134 (the a/c was dead in all three but I didn't use it until now), and it's been different with each of them. The Golf does what it does, but the green Corrado blows pretty cold. I didn't notice it until I gave it a little exercise today, but the C's compressor is beginning to make a little noise as well. I used the R134 kit with the "compressor oil", but without the sealant. I can't help but wonder if it's just age though, they're both `92s.

    Haven't done the black Corrado yet, it's got other (electrical) things I've got to sort out before I can test it-and I haven't even checked the fuses yet..

  • John Brown

    June 25, 2009 3:58 p.m. John Brown MegaDork

    Mark, there may be some debris in the system clogging the orifice tube causing high pressure with a low charge.

    A thorough flush and refill may be in order.

    FWIW, when we did the AC conversion in that car we did it "the right way".

  • SupraWes

    June 25, 2009 4:30 p.m. SupraWes Dork

    You take a barely large enough to cool R12 system and convert it to R134 and its not going to work very well. Especially a place like hell, I mean florida.

  • bigbrainonbrad

    June 25, 2009 8:24 p.m. bigbrainonbrad New Reader

    Not to threadjack, but I have an A/C problem that hopefully can be diagnosed. The car is a 91 miata that has been converted to 134. I refilled the system and it blows cold as can be (haven't measured, but it is as cold or colder than the air in the g/f's smart). At low rpms the car sounds like a diesel when the compressor is enganged. As the rpms increase the diesel sound goes away but there is still a noise coming from the general area of the compressor. In my past experiences when a compressor was dead or dieing, the cold factor was non-existent unlike this car. The system had not been used in quite sometime and this was not a pro job by any stretch. Bought some oil and refridgerant popped it in and bam cold air, but the noise is embarassing. Sounds like I'm driving a tractor!!!

  • friedgreencorrado

    June 26, 2009 2:05 a.m. friedgreencorrado HalfDork

    Sounds like something similar to mine, brad. Didn't have the noise before filling with R134, but didn't use it for a long time after the R12 ran out.

  • 44Dwarf

    June 26, 2009 5:59 a.m. 44Dwarf Reader

    134 and R12 have slightly different sizing formulas 134 don't carry as much heat so an r12 system converted still has undersized evaporator and condenser for 134 usage yes it works but not as good as the r12 did.

  • friedgreencorrado

    June 26, 2009 10:47 p.m. friedgreencorrado HalfDork

    44Dwarf wrote:

    134 and R12 have slightly different sizing formulas 134 don't carry as much heat so an r12 system converted still has undersized evaporator and condenser for 134 usage yes it works but not as good as the r12 did.

    Okay, that makes sense. Thanks for the tip!

 

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