Charging a new A/C system

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da_raabi

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No more oil, but I did wonder if it possibly just needed more time to allow the refrigerant to enter. Not positive from your description that there was a problem yet (except for the low port issue, Jesse covered that). However, the variable orifice tubes don't have a good reputation.

So the crazy high low side pressure, and frosted over lower evap tube was normal for a low freon situation?

How long should it take to suck in the freon? I swear I was working on it for an hour and I maybe got 12-16oz of freon into the system. It seemed to take forreeevvveeerrrrr.

Again, I appreciate all the help guys. This is my first A/C project - so bear with me on this stuff! I've rebuilt transmissions, suspensions, 100% frame-off rebuilt my Camaro... but A/C? I've got nothing (yet).
 

CorvairGeek

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So the crazy high low side pressure, and frosted over lower evap tube was normal for a low freon situation?

How long should it take to suck in the freon? I swear I was working on it for an hour and I maybe got 12-16oz of freon into the system. It seemed to take forreeevvveeerrrrr.

Again, I appreciate all the help guys. This is my first A/C project - so bear with me on this stuff! I've rebuilt transmissions, suspensions, 100% frame-off rebuilt my Camaro... but A/C? I've got nothing (yet).

You may very well be right.
I know that dispensing refrigerant will give you an abnormally high, low side pressure. If you close the tap, you will see an immediate drop. Yours sounds too high though.
They do act strangely with low refrigerant levels, but I am highly suspicious of a variable orifice. I would love to use one myself, but too many stories of failure.
Too me, R134a does dispense painfully slowly compared to R12, but your time does seem excessive. The entire charge should have gone in during that time, but the excessive low pressure is keeping it in the container.
 

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134 takes forever
I just buy extra cans and when about half the can is gone and it stops going in ,
I toss it and use a new can
 

da_raabi

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134 takes forever
I just buy extra cans and when about half the can is gone and it stops going in ,
I toss it and use a new can

Ok, that makes me feel better. I resorted to doing just that and was wondering what the hell I was doing wrong.

Part of my problem was a lack of adapters for the freon cans. This EPA valve thing made life very difficult. I know you guys mentioned this, but I figured the gauge kit would come with everything. Turns out it came with NOTHING. A quick jury-rigging later, and I was able to do at least something. A friend of my Dad's is going to loan me an adapter to make it work for round two though.

The whole thing was a **** show lol.
 

da_raabi

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Next update: success!

I got a different can adapter that worked a LOT better, and allowed the sensor to cycle the compressor on it's own. I was able to get about another can full in it before it started cycling. I keep going until the pressures looked ok. See pic below. Considering it was over 100 degrees today I'd say it was blowing pretty dang cool!

Now as long as I don't have any leaks I should be good to go!

Thanks for all the advice everybody!

You must be registered for see images attach
 

DoubleDingo

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Congrats!
 

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Glad you've got cool, dry air now!
 

da_raabi

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All fun and games until you blow the engine. Litteraly the morning after I finally got the AC working (it took 6 years) the engine wiped the timing gear. I had started in in the driveway to see if the AC leaked overnight. It ran like crap for two minutes, then died. Here's the damage. Yes, I found bent pushrods too...
 

da_raabi

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Hmm. Can't upload pics from my phone. I'll try again on my PC tomorrow.
 

Blue Ox

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My heart goes out to you. We seem to have similar "luck".
 

DoubleDingo

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That really sucks! One step forward, three steps back.
 

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