I have a ten year old Taurus. The first seven years the AC was like
new, but after that I've had repair done for the last three summers
(leak sealing procedure and cooling agent replaced). It's happening
again this summer. I used it three or four times and it's only
What can be done? Can this AC be restored to new? Is it normal to
need repair every summer?
Joek In Jersey
It will keep happening until you actually make the repair. The "leak
sealing procedure" is less than a band-aid - it will never "heal".
On the Taurus, the "Condensor-to-Evaporator Tube" is the usual suspect,
especially when you can't easily find the leak. It runs along the right
side frame rail in the engine compartment, covered in a foam insulator tube.
Depends on what the "leak sealing procedure" was. If the crankshaft
bearings in the AC compressor are shot and wobbling, or the shaft is
scored where it goes through the seal and it leaks even with the seal
replaced, it's time for a remanufactured compressor.
All the components and hoses are replaceable, it's in the labor
needed to correctly identify the problem part(s) and replace them -
without breaking something else.
The only place that sealants can be used is on the joints between
lines and hoses (LineLock sealant, works like Permatex #2) and that's
only a palliative - you're supposed to replace or re-anneal the soft
copper gaskets, or change out the line that has a cracked/scratched
flare sealing surface.
Sealant compounds that go in the refrigerant (like Bar's Leak in the
radiator) can't work - they would clog the small channels in the
metering orifice (or expansion valve) that would look just like a big
leak to anything floating through. Or get caught in the filter/drier
You have to be Very Careful with the fittings on the refrigerant
lines and the cores, if you don't use two flare-nut wrenches correctly
the aluminum tubing twists and it's all over. Aluminum will develop
fatigue cracks when bent and Pssssssss...
The evaporator core is the one killer component - it's in the heater
box, and in most Fords you practically have to dismantle the entire
dashboard and interior of the car to change them. If you have to do
that get a new heater core installed at the same time, because
Murphy's Law says next year it springs a leak.
--<< Bruce >>--
The only reason it may be more prevalent is that R-134a normal
operating pressures are much higher than R-12. I don't have the
charts handy, but from memory it's something like a jump from 180 PSI
on the high-side of an R-12 system to 300+ PSI for R-134a.
That, and they may be trying to use the same thickness of aluminum
tubing for the cores and connecting lines of newer cars (or even
shaving a few thou off the wall thickness to save weight and money)
even with the higher running pressures. Which would make them a bit
more likely to develop little porosity leaks and/or fatigue cracks and
Haven't stopped to research it, though.
--<< Bruce >>--
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