A/c check
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A/c check
I have a 91 F150 4.9 The AC has quit cooling. The compressor cycles and I have added freon but it seems to leak off quickly. It was converted to 134 about six years ago. How is a diy leak check done? Is there any special equip required?
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also look for any oil soaked joints or fittings. hard to beat the soap though, i work on refrigeration units on trucks and use soap for leak testing daily, the fancy electronic leak detectors just collect dust in corner.
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I would like to learn more about dealing with AC.
lets say I find a couple leaks in the system, on say a couple of tubes. Could it be as easy as removing the refrigerant from the system, replacing the leaky tube or seal, and recharging?
I have never really dealt with AC, my stepfather has the basic equipment to charge it etc. AC is just one of those things that stayed foreign to me on a vehicle. This year I would really like to try to fix my ac in my truck, its 134a, so no need for conversion.
lets say I find a couple leaks in the system, on say a couple of tubes. Could it be as easy as removing the refrigerant from the system, replacing the leaky tube or seal, and recharging?
I have never really dealt with AC, my stepfather has the basic equipment to charge it etc. AC is just one of those things that stayed foreign to me on a vehicle. This year I would really like to try to fix my ac in my truck, its 134a, so no need for conversion.
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Two more questions, to find a leak, I see you say to use soap and look for leaks.
Now would the Compressor run without freon? or is there some kind of safety thing on the compressor to prevent damage from low freon.
And I assume to find leaks, you would need to refill the system with freon?
Now would the Compressor run without freon? or is there some kind of safety thing on the compressor to prevent damage from low freon.
And I assume to find leaks, you would need to refill the system with freon?
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there should be a low pressure switch to keep the clutch from engaging when charge is low, usually a low charge can be heard by the rapid cycling of the clutch.
some times the fitting or seal is as easy as an o-ring but could be rotted pipe or a hole in the condenser.
to recharge the system after its been drained you will have to pull it into a vaccum to get all air and moisture out as this will cause high pressure symptoms and if these have a high pressure switch they will cause cycling of the cluch as well
some times the fitting or seal is as easy as an o-ring but could be rotted pipe or a hole in the condenser.
to recharge the system after its been drained you will have to pull it into a vaccum to get all air and moisture out as this will cause high pressure symptoms and if these have a high pressure switch they will cause cycling of the cluch as well
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What equipment do you use to "pull it into a vacuum"? Is there any way around this, I assume if the system has been sitting dead for months perhaps years this would be even more important?
Is the moisture caused by going from being charged, to empty, kind of like condensation inside?
To recharge, do you simply recharge the system once its been 'cleaned' or is this something you do at the same time, kinda like a flush.
Let me know if my questions are annoying
Is the moisture caused by going from being charged, to empty, kind of like condensation inside?
To recharge, do you simply recharge the system once its been 'cleaned' or is this something you do at the same time, kinda like a flush.
Let me know if my questions are annoying
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a vaccum pump is used, not really an everyday tool but most shops that do a/c have one or any one that does a/c and refrigeration. the moisture is caused by sitting empty, and being attracted to the oil
the recharge is done after the system is in a vaccum and you put the proper charge in
iam not sure how the system would perform if a charge was just put in and i dont think there is any other way to pull a vaccum. there are many gov regulations where i live so most a/c work gets done by a shop because of having the equipment.
if any more questions fire away.
the recharge is done after the system is in a vaccum and you put the proper charge in
iam not sure how the system would perform if a charge was just put in and i dont think there is any other way to pull a vaccum. there are many gov regulations where i live so most a/c work gets done by a shop because of having the equipment.
if any more questions fire away.
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Galizien, Thanks for asking those questions as they were also item I was wising to know. I did not think of the obvious (soap bubbles) which is how I leak check gas lines at work. If you want you can get a product called Snoop at industrial supply which is basically the same thing. Just so happened that my sons' Toy is having the same problem today. We live in So TX where AC is already needed. Rusty and Kansas Mike......Thank you for your input.
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I've had good luck with the soap and water method myself. I've also had good luck with the ultraviolet dye as well. Most of the time if I'm doing a conversion or repair work, I'll put in can of dye in first and then the 134A from a 30 lb. drum. That way if it's leaking all I have to do to find it is close the doors, deck the lights and fire up the UV light.
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Originally Posted by rusty90f1504x4
iam not sure how the system would perform if a charge was just put in and i dont think there is any other way to pull a vaccum.
As rusty pointed out, the moisture collects in the oil. Keep in mind that when you pull a vacuum, it only removes the moisture, not the oil.
I paid $300 for my vacuum pump (6CFM, dual-stage), but most DIY'ers wouldn't use it enough to warrant the cost.