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Discussion Starter #1
does anyone know how often the compressor on the ac should cycle on and off. the air is cold but i just refilled it and i dont know how often it should cycle on and off.
 

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It depends on the outside temperature/humidity as well as the interior temperature. I do not have a photo of the cycling curve from my Ford Service CD to show what it should be. If you charged by weight you will know if the pressures are within range, that is the true deciding factor to me.
 

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Discussion Starter #3
It depends on the outside temperature/humidity as well as the interior temperature. I do not have a photo of the cycling curve from my Ford Service CD to show what it should be. If you charged by weight you will know if the pressures are within range, that is the true deciding factor to me.
by weight? my thermometer said 100 degrees although it was in the sun so im guessing it was 85-90. i had the doors open too. the humidity is high since its florida. i got a can with the gauge on it. i got it to the point where the needle was always in the blue (full) space.
 

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To get the drift of what rla2005 is telling you....start the engine, turn the AC up to max-cool and watch your gauge while spraying cool water against the condenser core. You'll see the low side pressure drop considerably. You'll also note a change in cycle rate. Same thing happens as you increase engine RPM, which causes the compressor to draw faster.
Just from those two things you can see how changing conditions effect pressure & cycle rate. In other words, there aint no answer to your question.
What you need to know most is how full the system is. You need a real set of A/C gauges for that. The little make believe gauge that comes in a 1-can freon kit aint actualy telling you anything other than if you're making some sort of progress or not.

DGW
 

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Discussion Starter #5
To get the drift of what rla2005 is telling you....start the engine, turn the AC up to max-cool and watch your gauge while spraying cool water against the condenser core. You'll see the low side pressure drop considerably. You'll also note a change in cycle rate. Same thing happens as you increase engine RPM, which causes the compressor to draw faster.
Just from those two things you can see how changing conditions effect pressure & cycle rate. In other words, there aint no answer to your question.
What you need to know most is how full the system is. You need a real set of A/C gauges for that. The little make believe gauge that comes in a 1-can freon kit aint actualy telling you anything other than if you're making some sort of progress or not.

DGW
well i filled it last night and this morning its warm again.
 

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Then I would say you have a leak
 

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To get the drift of what rla2005 is telling you....start the engine, turn the AC up to max-cool and watch your gauge while spraying cool water against the condenser core. You'll see the low side pressure drop considerably. You'll also note a change in cycle rate. Same thing happens as you increase engine RPM, which causes the compressor to draw faster.
Just from those two things you can see how changing conditions effect pressure & cycle rate. In other words, there aint no answer to your question.
What you need to know most is how full the system is. You need a real set of A/C gauges for that. The little make believe gauge that comes in a 1-can freon kit aint actualy telling you anything other than if you're making some sort of progress or not.

DGW
Exactly! :beer
 

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Discussion Starter #8
well the one thing i think might have been the problem is the manifold that attatches to the compressor. it seemed like it always was kinda loose:duh. well last night after i got done seafoaming the engine i bumped inot it and i could hear air escaping. if i moved it just a tad bit it would start leaking. so i took a wrench and snugged the bold down, not tight just snug and it doesnt move and wont leak anymore. i didnt start the truck till this morning:whiteflag. the air was kina cool but not really cold. when i put the gauge thing on it it read slightly below where it was at before.so i put a little more in and now its cold again.the needle is only up less than a mil than it was before i filled it this morning. the whole reason im doing this is because the high pressure port started leaking and leaked out all my refrigerant.:whiteflag


how much will a shop charge me to check the freon level. keep in mind im in florida and shops seem to charge out the ass for this stuff.
 

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I have not been to a shop for A/C work in over 15 years so I cannot answer that question. If you have items that leak it could get pricey to have someone else track down all of them. If the ports leak replace the valves. If that is the case when the system is empty replace every o-ring you can find. I purchased a universal o-ring kit for a few dollars at the local parts supply last summer when I repaired the A/C system on my '92 F350. I replaced the condenser, receiver/dryer, orifice tube and the liquid line for under $250. I changed all of the o-rings on the other fittings while I had the system apart. I recharged it with R-406A (Auto Frost) because I had several cans left over from another project.
 

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Discussion Starter #10
I have not been to a shop for A/C work in over 15 years so I cannot answer that question. If you have items that leak it could get pricey to have someone else track down all of them. If the ports leak replace the valves. If that is the case when the system is empty replace every o-ring you can find. I purchased a universal o-ring kit for a few dollars at the local parts supply last summer when I repaired the A/C system on my '92 F350. I replaced the condenser, receiver/dryer, orifice tube and the liquid line for under $250. I changed all of the o-rings on the other fittings while I had the system apart. I recharged it with R-406A (Auto Frost) because I had several cans left over from another project.
it must be a leak, i filled it this morning and now its not cooling again. this is so frustrating, i had no leaks until that damn valve started leaking and now it wont hold a charge. i replaced the port too.
 

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If there is any pressure left at all try using a spray bottle filled with warm soapy water and spray each connection then look for bubbles. Bubbles are bad, there is your leak(s). Don't be surprised if you find the connections good, it could be a hole in the condenser. On my '92 it was the condenser outlet tube leading back to the evaporator that had cracked and broken off.

Yours is leaking at a pretty good rate, you should be able find the leak with the soapy water and a visual inspection. It's the slow leakers that require a halon detector (sniffer). I managed to score one last year for $25 on E-bay :beer
 

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Discussion Starter #12
If there is any pressure left at all try using a spray bottle filled with warm soapy water and spray each connection then look for bubbles. Bubbles are bad, there is your leak(s). Don't be surprised if you find the connections good, it could be a hole in the condenser. On my '92 it was the condenser outlet tube leading back to the evaporator that had cracked and broken off.

Yours is leaking at a pretty good rate, you should be able find the leak with the soapy water and a visual inspection. It's the slow leakers that require a halon detector (sniffer). I managed to score one last year for $25 on E-bay :beer
one thing im wondering, it leaked all the refirgerant out and i had the port off for a while. im wondering if it has something to do with air being in the system. i hoping maybe the air is getting purged out or absorbed or something and thats why it only needs a little freon to be cold again.
 

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its got a leak somewhere.. Check the bottom of the condenser as they will rub a hole in the bottom tube on the passenger side. Ive seen it 3 times. you can jumper the low pressure switch temporarly to get a little pressure to check for a leak... Spray bottle filled with soapy water.
 

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Once an A/C system has been opened to the atmosphere, it's best to have it vacume-downed through a set of gauges so's you'll know how much vacume it will hold, and for how long. If done proper, the vacuming proccess will also remove the moisture from within the system.
All of those are nessesary things. None of them can be done without proper equipment.

What I'm saying is that if you're going to do your own A/C work, you'll be way ahead of the game to buy the equipment it takes. Otherwise you're just stabing around in the dark.

Just my 02 .

DGW
 

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Discussion Starter #15
im thinking my best bet is to take it to a shop. see if theyll let me use a uv pen and glasses since it already has some dye in it. if there are no leaks have them vacume it out and charge it back up:thumbup. if its $30-$40 i should have done it in the first place since it cost me $40 in refrigerant to fill it:doh0715:.
 

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Discussion Starter #16
its got a leak somewhere.. Check the bottom of the condenser as they will rub a hole in the bottom tube on the passenger side. Ive seen it 3 times. you can jumper the low pressure switch temporarly to get a little pressure to check for a leak... Spray bottle filled with soapy water.
it will turn the compressor on and off, and cool. its just that once it sits for a while it will no longer blow cold air unless i fill it more.
 

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Discussion Starter #17
just an update, i filled the ac back up again last night and it was ice cold. went out this morning and it was ice cold. should i still get the system evacuated and recharged. the refrigerant i used did have a moisture and acid eliminator in it.
 

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If it were mine AND I planned on keeping the truck for awhile I would do the job right. But then again I have all the tools now to do it myself. Run it for a few weeks and see what happens. If it leaks down again, get the tools or take it to a shop.
 

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Discussion Starter #19
If it were mine AND I planned on keeping the truck for awhile I would do the job right. But then again I have all the tools now to do it myself. Run it for a few weeks and see what happens. If it leaks down again, get the tools or take it to a shop.
im wondering if maybe something absorbed the air or something:scratchhe. if it isnt much i may just have the ac evacuated and recharged. that dye that i put in had a stop leak in it(only one that i could put in with it under pressure). i put that in a filled it and its been cold since. i figure if i do get it evacuated ill have them look around with the little light and glasses and see if they find a leak. part of me thinks maybe the new highside port needed the orings to get lubricated/swell up to seal well and thats why it leaked::shrug. regardless im in florida so no ac is not acceptable.:duh
 
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