1991 Dodge AC

[xylorex]

My father-in-law acquired a 1991 Dodge Spirit R/T (2.2 liter twin cam, 4 valve per cylinder, intercooled turbo, 5-speed getrag).

He brought it over for me to do some work to, I've knocked about everything out except for the air conditioning. I have replaced ever component except for the hoses, can't get it to cool... What the lines do is get hot as hell! I've tried r-134a first (originally r-12 system), then when I had no luck with that I tried r-12a. Never had one give me this much trouble.

My question is -- have any of you experienced a hose causing these symptoms?

Thanks

 

[xylorex]

Guys, I know the topic isn't sexy being a 4 cylinder dodge and all... But i would appreciate it if a few of you could chime in on your experience with AC hose failures.

not leaking failures, but whats happened to you when the interior of an AC hose has failed / deteriorated.

 

[DRIVEN]

What are the gauge pressures?

 

[Turbolq4]

I thought those were single cam?? I'm no help on the a/c front, sorry.

 

[xylorex]

I thought those were single cam?? I'm no help on the a/c front, sorry.

nope, twin overhead cams! https://www.allpar.com/model/spiritrt.html

 

[xylorex]

What are the gauge pressures?

thanks for your reply driven.

to be honest i don't remember exactly what the low to high side ratio was... but the compressor is new and working.

however i did several times pull vacuum for 2+ hours and re-charge up to 20psi or so and slowly add until about 40 psi on the low side. around the upper end of this range the line would get "cool", but not enough to produce any condensation (charging with my hand on the low size). then i would slowly bleed off a little at a time to try and find a sweet spot (usually 15psi or so), but after this the line temperature just keeps getting hotter and hotter no matter how much i add or remove. (recirc on/ blower motor on high / ~1200 rpm / squirrel cage fan blowing in front of condenser)

so, i thought that maybe it was the metering valve... i thought that perhaps since it was designed for r12 that the r134a wasn't flashing. i changed the dryer and pulled vacuum on it for several hours. did same procedure as above for the r12a but had the same result.

i've done the r134a probably 3 or 4 different times, and the r12a twice. kinda tired of throwing cash around at it!!

 

[DRIVEN]

Sounds like you covered most of it. My limited experience with conversions is that they take about 80% R134 vs R12.

Maybe a stupid question; is the cooling fan cycling?

 

[xylorex]

Sounds like you covered most of it. My limited experience with conversions is that they take about 80% R134 vs R12.

Maybe a stupid question; is the cooling fan cycling?

Yes, the electric fan comes on when the AC compressor clutch is energized

 

[DRIVEN]

Since you're listing PSI, I assume you're not charging by weight, correct? If so, that's always tough to dial in. If your oil spec is close, the compressor itself shouldn't get very warm but H line will. I'd think 140-ish. L line should be cold to the touch.
I kind of suspect you're under filling but without knowing the weight of the charge or seeing gauge readings, that's only a guess.
Sorry if that's vague. AC is one of those things that's tough to diag via keyboard. Here's a little cheat sheet if you don't already have one.

AC System Pressure Chart - A/C recharge kits

rechargeac.com

 

[Turbolq4]

nope, twin overhead cams! https://www.allpar.com/model/spiritrt.html

Well sumbeech!!