The car: 85 300td
Problem: AC 134a keeps leaking out of the system, can not find the dye...

I have replace the evaporator (saga), the stem in the replacement valve, and the expansion valve...

The system looses the 134a in about a week, fast if the car sits for any period time(like in 3 days). I have loaded the system with dye but I can't find the leak...

Can the 134a be leaking out of the compressor without the dye coming out, and could it leak out that fast???

Thanks Jason

Can the 134a leak out

No and yes.
The dye is coming out.
It can leak that fast.

Compressor shaft seal is possible, but I had a PIA FORD many years ago, condenser started leaking on the back = radiator side = very hard to find, radiator failed, and I found the leak during R&R.

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1985 300SD
1983 300D
1984 190D
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2002 Honda Civic

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Was it a NEW evaporator??
That would be a place a leak wouldn't be visible.

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'05 Acura TL 6MT
2001 ML430 My Spare

Gone:
'95 E300 188K "Batmobile" Texas Unfriendly Black
'85 300TD 235K "The Wagon" Texas Friendly White
'80 240D 154K "China" Scar engine installed
'81 300TD 240K "Smash"
'80 240D 230K "The Squash"
'81 240D 293K"Scar" Rear ended harder than Elton John

Was that evaporator both pressure adn vacuum tested for leaks BEFORE it was installed?

I have read where new ones can leak one way and not the other.

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"He who fights with monsters might take care lest he thereby become a monster. And if you gaze for long into an abyss, the abyss gazes also into you." - Friedrich Nietzsche

I have another thread on this that was closed.

I took it to an indy here in Houston, who thought the evaporator was leak, after I had replaced it. So I took it out again and had it leaked checked. It was fine.

When I redid the AC box I installed a clear tube, think that it maybe function in the future if I needed to inspect the water coming out. Well there was some dye left in the AC box from the old leaking evaporator that drained out with the condensation. The mechanic thought that was a new leak, ie the new evaportator was leak...but it was not.

So several weeks later and 10 cans of 134a, and it is still leaking, but I can't find it.

I have checked the hoses, condensor, evaporator, expansion valve, all the connections, and the compressor. My old thought is somehow the 134a is leaking out without the dye coming out.

The AC has been working now for 2 weeks, but it is statring to lose its cooling ability now. Just thought I would ask some question before I really inspect it on Friday...

The best way to diagnose tough to find leaks is by putting in a couple of ounces of R22, then pressurize the system with nitrogen, then use an electronic leak detector. This does several things; it pressurizes even the low side system and makes the electronic leak detector much more sensitive because R22 is much more detectable with one of these gadgets.

The EPA even allows you to vent the two ounces of R22 because they realize that this will polute much less than a leaking system.

I doubt that you are equipped for this method, but there should be a good auto a/c or commercial/residential a/c shop near you that is equipped to do this. The nitrogen/R22 method is very commonly used by the commercial/residential boys.

Good luck,

I find a shop that can do it...

A blacklight from Wal-Mart etc., is extremely helpfull for chasing freon leaks and looking for scorpions if you live in TX.

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00 E420
98 E300 DT
97 E420 Donor Car - NEED PARTS? PM ME!
97 S500
97 E300D
86 Holden Jackaroo Turbo D
86 300SDL
(o\|/o)

What's the scorpion deal? Do they light up? or is the blacklight just a vision aid at night instead of sending them scuttling away with a regular light?

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The Golden Rule

1984 300SD (bought new, sold it in 1988, bought it back 13 yrs. later)

Yes, they all light up....
but they can't see the black light... so it is used to harvest them...

http://www.thebestcontrol.com/bugstop/control_scorpions.htm

They glow in the dark, bright white....Can't remember if they still glow after you smush 'em though......

PS....I don't think this test works on Rattlesnakes....

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1998 W202 C230 - The money pit of late.
1984 W126 300SD (356,800 miles) Gone to the wrenchapart
1984 W123 300D Gone to the wrenchapart
1972 W108 280SE 3.5 (sold but not forgotten)
1986 Buick Grand National 3.8l Turbo (86k miles)
1966 Glassic Model 'A' Replica http://www.glassicannex.org

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Make them easier to hunt

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BENZ THERE DONE THAThttp://www.peachparts.com/shopforum/...c/progress.gif
15 VW Passat TDI
00 E420
98 E300 DT
97 E420 Donor Car - NEED PARTS? PM ME!
97 S500
97 E300D
86 Holden Jackaroo Turbo D
86 300SDL
(o\|/o)

But not sure I have many of those in downtown houston.

Don't bet on it. Houstons heat and humidity provides a haven for these evil little critters.

Have a great day,