UV Dye Work If System Has A Leak And Compressor Not Kicking On?

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cloves
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UV Dye Work If System Has A Leak And Compressor Not Kicking On?

Post by cloves »

HI all,

I have Mazda 3 that has had an odd leak for a year now. A month ago as the summer rolled in I evacuated the system at a shop. I then took the car and vacuumed the system for 30 minutes and let the system sit for an hour to make sure it was leak free. I then refilled the system and the A/C was ice cold for over 3 weeks. I then parked the car in the driveway for a few days (Very small pitch on the driveway). Today the car's compressor was not kicking on. I know I have a small leak somewhere, I am imagining that the small pitch must be causing the freon to leak a higher rate. The car has been parked on flat ground everyday for 3 weeks no issue until this past week.

Now I picked up an dye/oil injection system that lets me add oil or dye manually, no gauges needed (I have the gauges mind you). But since the freon pressure is not high enough now (Since the compressor isn't kicking on), will putting dye i the system work without raising the freon pressure back up to the point where the compressor kicks on and cycles?
GM Tech
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Re: UV Dye Work If System Has A Leak And Compressor Not Kicking On?

Post by GM Tech »

You are worried that pressure is not high enough? and it needs to run to generate high pressure? You must think your leak is on the high side. - The low side pressure will actually drop when compressor runs- you have a good chance the leak is on the low side- so running compressor would drop the pressure on that side of system.. Bottom line- the dye works- even at static pressure- where both high and low sides are the same pressure....
cloves
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Joined: Sun May 21, 2017 5:50 pm

Re: UV Dye Work If System Has A Leak And Compressor Not Kicking On?

Post by cloves »

GMtech, thanks for the reply.

I am worried the dye won't cycle inside the system since the freon level has dropped now till the point the compressor won't kick on. Which makes me want to think in order to have the uv oil dye cycle I will have to also add enough freon so the compressor kicks on. Which then makes me think I will have to go to the shop have them evac and then come home vac and refill the system and add dye into the line as well.

The Mazda 3 (07) is a bit of an odd bird. When I vac the low and high lines I have to add about 8oz to the high size (car off) and then car on and add the rest to the low side. The only way the compressor will turn on if it has freon on the high side, no way around that.
xtal_01
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Joined: Tue Jun 27, 2017 7:59 pm

Re: UV Dye Work If System Has A Leak And Compressor Not Kicking On?

Post by xtal_01 »

I believe you are exactly correct.

If you simply put the die in, it will not circulate and thus not leak out.

I just watched a video (thinking I was going to have to do this a couple days ago) and it said to add dye as well as freon to get the pressure high enough to kick on and circulate the dye ... as well as to "push" it out through the leak.

In fact it said that if the leak is very small, you may have to drive the vehicle around for up to a week to let enough dye leak out in order to see it.

As I said, I was about to do the same thing to find a leak. Went to put in the dye ... tag on the suction connection "factory filled with UV dye". Took my glasses and light around the van, found the leak in less than 5 minutes! Now I am still trying to fix it but that is another very long story.

Hope this helps ..... Mike
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