anti freeze dye?

optionizerSS

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Have a very small AF leak so added some dye to the coolant today. Problem is it usually takes 3 or 4 days for the leak to show itself. If the dye dries will it still show under the
UV light or does it still have to be liquidy?

Looking to order a UV light but might take a few days to get it. Concern is if the dye dries I will have to go drive it around again and it is supposed to start snowing this week.
 

cobrajeff96

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Sounds like the leak orginates further up top, like near the head area or the heater core-to-block interface. Then it'll trickle downward. In my experience, the dye mixes pretty well with the medium, so it should show up pretty easily. Just don't get a little pen light, get something with a little grunt behind it. They even sell UV lights about the size of you first that have 12v alligator clips on them sort of like jumper cables but smaller.
 
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optionizerSS

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It's hard to pinpoint. It takes a few days to see anything on the floor and I have only seen it on the engine way back in mid summer. There are 2 flat spots on the front of the 5.0 on each side of the timing cover. One time I saw puddles on each of those flat spots but that was the only time I ever saw anything up near the top. When under the car I can see it dripping from the front and sometimes rear of the oil pan rails
Playing with my UV light just now I got it to flick on so ran out and checked and nothing. I took the rad cap off and can see where some of the dye spilled so the dye is doing its job.
There are only 2 spots that 'lit' up. One was a plastic push pin under the hood so guessing something in the plastic is triggering it cause where it is it definitely isn't the dye. The other is the plastic on the oil pressure sensor so guessing some plastics light up too. Other than that nothing is illuminating after about 20 hours.
 

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I guess it's obvious but worth mentioning if you drive it any speed the headwind will be splashing the drips around so could be tricky to follow it back to the exact source.
 
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optionizerSS

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Checked it over again tonight. Don't see anything up top except a very slight hint of something illuminating at the corner of the intake but there are a few drops on the floor. From underneath I can see dried spots lighting up on the AC pump like maybe it was flung onto there. But there is obvious wet dyed AF where the timing cover meets the oil pan. The drops on the floor are right under that. I don't see anything any higher up but have never seen water in my oil either.
Also, last summer I had about a teaspoon full of AF puddling on the flat part at the top of the timing cover so that leads me to believe it is coming from higher up.
Gonna try to get a better UV light and get a better look and have a 2nd set of eyes look at it too.
Thoughts?
If it is the timing cover leaking how big of a job is that? I have the tools and equipment and used to build engines, just trying to prepare myself for this task if thats what it is.
1995 GT 5.0
 

cobrajeff96

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Also bear in mind that UV dye is typically added to R134 for A/C. Make sure it doesn't come from anywhere in the A/C system too. Lots of connections points, unfortunately.
 
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optionizerSS

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Good point. That might be old UV dye or could just be some odd oxidation reacting? I had a couple of plastic pieces light up too that I know had no dye on them but it wasn't the same color as the dye I saw at the front of the pan
 

cobrajeff96

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Like someone else said, the slipstream entering the front of the car is kind of a bastard for pinpointing leaks after a drive above 45mph.
 
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optionizerSS

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Like someone else said, the slipstream entering the front of the car is kind of a bastard for pinpointing leaks after a drive above 45mph.
Don't think i went over 45. There is one stretch where i may have hit 45-50 but the rest was all in town at 15-20 mph. but i got the RPMs up to get heat in it to be sure the t-stat opened but the AC compressor is the only place i see anything lighting up .
aside from that, it never seems to leak when its running. i put 4000 miles on it this summer and only had to add less than a quart of AF
 

cobrajeff96

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Shouldn't have to add any, fact remains.

If the dye is showing up puddled around the A/C, you might have to investigate A/c lines or the compressor itself. Even though you may not activate it, doesn't rule out a failure completely. I had an A/C compressor lock up so hard that the engine couldn't be cranked and the unit hadn't been turned on in a year or two. Shit happens, as they say. And sure enough right before I decided to R&R the compressor, on the drive to a shop it literally blew up.
 
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optionizerSS

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no puddles near AC. just looks like the dye might have sprayed up on the compressor. The only puddles are a few drops on the floor right under the front lip of the oil pan and once last year the flat areas on top of the timing cover had 2 little puddles
 

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