I’m having trouble finding a leak in my A/C System. All Freon was lost, but I can’t find any indication of oily residue. I’m confused about how to determine if the evaporator is leaking. According to my manual, I understand you first have to break the lines to remove; do you do a bench test? My manual says (Note: Before replacing the A/C evaporator core it is mandatory that an on-vehicle leak test be performed.). I have put dye in the system and was using a pin test light from AutoZone. Do these lights work or should I get something else? All pressures are good, temperature at vent registers 33°. I know this is just temporary. I’m new to this; some expert advice sure would help.
96 RANGER 4 CYL 2.3 5 SPD
Further down the main page in the forums is a section under "Misc" labeled "cooling, heating, ventilation and A/C" that would get you way more answers and attention.
I don't know about a 'pin' light. Most leak detectors will show up under a 'black light' which you can buy and install into a 'trouble light' or 'drop light' and then use to inspect for dye.
When they say 'break the lines' they mean use the 'special' tool to disconnect the fittings. If your evap is bad, you might find dye in the outlets under the dash or in the condensate drain protruding from the firewall or plenum on the engine side (where the water leaks out...)
You could use a sniffer, also, to check the evap. It is a bear to r&r because you have to drop the dashboard to remove the plenum.
tom
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Tom,
Thanks for your reply. The pin light is a black light it came with goggles for around $13.00. I’m not sure how good it is. Ford recommends using an electronic leak detector.
I’m going to find one today. Btw, I found the test procedure in my manual, there is so much information it’s very hard to get around, but I’m learning slowly. When I check it out again I’ll let you know the outcome.
Johnny
I’m having trouble finding a leak in my A/C System. All Freon was lost, but I can’t find any indication of oily residue. I’m confused about how to determine if the evaporator is leaking. According to my manual, I understand you first have to break the lines to remove; do you do a bench test? My manual says (Note: Before replacing the A/C evaporator core it is mandatory that an on-vehicle leak test be performed.). I have put dye in the system and was using a pin test light from AutoZone. Do these lights work or should I get something else? All pressures are good, temperature at vent registers 33°. I know this is just temporary. I’m new to this; some expert advice sure would help.
96 RANGER 4 CYL 2.3 5 SPD
Thanks in advance,
Johnny
IM confused a bit, you said all pressure was lost now all pressures are good and its blowing cold?
Did you ever pull a vacuum on the system? Thats the easiest way to find a leak. You can rent one from auto zone for free, just got to put down a deposit. It might not have leak if it was just a little low or did you say all pressure was lost? I need clarification on that, im confused on how you lost all pressure but you recharged and now its blowing cold. Guessing a slow leak...
AGGIE,
Thanks for your reply. I know why you were confused; when I looked back it confused me, too. Sometimes you don’t say exactly what you mean. I meant that after I charged the system everything was OK, but, no, I did not pull a vacuum on the system. I don’t remember exactly what the readings on the gauges were before I put Freon in it, but I believe it was close to 80 low, 80 high & 80 ambient. I am determined to learn how to do this right, hopefully with the help of people like you. Please bear with me. fficeffice" /> > >
Thanks again, > >
Johnny > >
I forgot to say it’s still cooling as good as when it was new. I’ve been driving it a lot in heavy traffic, outside temperature 95°, for a couple of days. Makes you think it must be a very slow leak.
Johnny
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