Need some Auto A/C help

[The Buddha]

Its a 97 F 150 with 4.6 v8 and an AC compressor bigger than most motorcycle motors (exaggerating but its big). The thing was a 134 system to start with. No R12-> BS here.
The original system had damn good power and would freeze you out of the car if you didn't shut it down after it got cold.
n 2005/6 that thing had a compressor go bad, which the guy that diagnosed it made a mistake and said it was evaporator core, then I had my mechanic non AC guy, remove the dash to get to the core, then I took it to an AC guy who said it wasn't the core after he removed it, and said it was compressor and by this time I was so far out $$$ I slapped in a rebuilt compressor and what ever else needed and it was back and working.

Except - it took a lot longer to cool, it never got deathly cold so we never turned it off etc etc.

Then earlier this year it died. And this time I had a damn good mech, who said get me compressor, orifice tube, condensor (or whatever that is that looks like a round aluminum can) and PAG and R134 etc and a new belt cos the old one smoked when the compressor died. I got new everything else and a remanufactured compressor.

OK, swapped it all in. Works ... like the thing did after the first time it was swapped. Not like original. Can anyone tell me what/why.

Cool.
Buddha.

[yamahonkawazuki]

is the 134/134a topped off?

[TheGoodGuy]

my understanding is that if the pressures of the R134 isnt set correctly it will under cool. Also check to see if your cooling fins on the condensor is clean.

I had an issue with TSX when the pressures were too high and it blew an escape valve. They had to refill, and it took 2 days of high heat (90+) to get the right amount of pressures. I'd start there the cold and hot pressures on the check valve side.

[yamahonkawazuki]

my understanding is that if the pressures of the R134 isnt set correctly it will under cool. Also check to see if your cooling fins on the condensor is clean.

I had an issue with TSX when the pressures were too high and it blew an escape valve. They had to refill, and it took 2 days of high heat (90+) to get the right amount of pressures. I'd start there the cold and hot pressures on the check valve side.

THIS makes a lot of sense Buddha. ALOT of sense

[The Buddha]

Plenty o 134, filled correctly, just filled last week.
So, OK I asked around, cos my mitsu also has deathly cold ac, and the issue was that the cars originally got filled with dupont 134. The 134 available off the street isn't as efficient. You have to run it to a lower pressure. 15 bar or so .... instead of 25 bar for dupont.
The factory switch is not adjustable, so I need a low pressure switch that can be moved to 15-16 bar cos the dupont 134 is not available easily.
Thanks guys.

Cool.
Buddha.

[yamahonkawazuki]

10-4

[goobydoo]

The condenser mounts behind your radiator in vehicles,the canister is called the accumulator/drier.

Did you have the system flushed with nitrogen? Generally when a compressor fails a flush,finished with a nitrogen flush is needed to clean out the residual burnt oils,dirt and metal particles from the failed compressor to prevent the new compressor from failing prematurely.  The nitrogen removes moisture that can mix with refrigerant and form acid that eats up lubricant,seals etc...Then orifice tubes,the accumulator and compressor all need to be replaced.

[cbrfxr67]

Intriguing stuff ac is.  i did my timing belt/water pump recently and manhandled the ac lines pretty good.  AC was still working til this past weekend when it barely cooled at all.  Checked with gauges last night and low is good but high side is low.  By the way, I don't know much about ac, but here at work I have every tool I could possibly need to fix ac.  So, reading up and learning a bit more to give it a shot.  Was going to fill it with a bit of the 'street' 134a you mentioned and see what it does.  If nothing, check for leaks and start trying to figure it out.  Should be interesting,.....

[yamahonkawazuki]

"Its something you take apart in 2-3 days and takes 10 years to go back together."
-Buddha

lol your quote cbr, I was digging through carport and found parts of my original gs. the subject of my first post called frankenbike. ( think post was let me introduce frankenbike) or something like that, I think was june 2003.

[The Buddha]

Goobydoo - I'll ask him about the nitrogen flush. But Its been working for 3 weeks now. I guess premature wear, we'll see if it happens.

The man put more refrigerant in it, just about 1/4 lb more. So there is now about 42 oz in a system that calls for 32. And its getting cold enough now that I need to turn it off a minute or 2 after about 20 min.
It still seems to be taking longer than I originally remember ...

Cool.
Buddha.