1999 Jeep Grand Cherokee A/C Problem

My dealer has been trying to solve my A/C problem since 8/04. They cannot
find the Freon leak. They have installed two new evaporators and recently
replaced the receiver drier. But the system still leaks Freon. It is a
slow/small leak. It takes about two weeks for the air to go from cold to
warm. It's summertime and I need my A/C. Any ideas?

 

Compressor seal?

I'm not an a.c. expert, but I would think two weeks to leak down is not
considered that slow a leak (i.e., should be detectable by normal
means). Have them put refrigerant laced with UV dye so that the leaked
residue can be spotted at the source of the leak. You can DIY, or take
it to an a.c. shop.

Bill Putney
(To reply by e-mail, replace the last letter of the alphabet in my
adddress with the letter 'x')

 

yes they need to get a sniffer instead of using a dye test
i now use both and have had great success finding even small leaks like in the
service valves

 

It takes practice to use a refrigerant sniffer properly to catch slow leaks.
Before I finally
started doing my own A/C the usual process I saw the corner mechanics doing
is to
park the car in the lot, idling with A/C running. That will only get the
obvious ones. The way
to catch the small ones is to park the car engine off inside a garage with
the door closed,
and clear everyone out except the person with the sniffer, and make sure
there's absolutely
no air movement. Then with the sensitivity at max, ever so slowly sweep the
system, all
hard and flex lines and all components, and make sure the probe is under the
line, not
above it, since refrigerant is heavier than air. The engine and ac system
should be hot.
And also sweep the evaporator inside the passenger compartment. This should
only be
done with slow leaks since refrigerant in an enclosed space can be
dangerous - it displaces
air and you can suffocate.

This process can easily take an hour or two to narrow it down, and might
also require
pressurizing the system with extra refrigerant (which should be removed
before the
compressor is started, of course) All in all not something most garages are
willing to
do unless you push them, since it's costly. And it's worthless unless the
leak detector
is really sensitive, which the cheapie ones are not.

I have never been a fan of the dye. Dye wicks along the outside of the pipe
and is
worthless to pinpoint exactly where the leak is, unless you look for the dye
right
after you put it in the system. And once you catch the leak you have to
clean the dye
off the outside in order to make sure there aren't 2 leaks really close to
each other.

Dye never was that popular until they started putting out UV dye, because
then the
customers couldn't see what a mess it made of the pipes and such inside
their
engine compartment.

Your probably losing an ounce a day, which isn't a slow leak. A slow leak
is something
like an ounce a month.

Ted

 

what a crock !!!!!!!!!!!!!!!
it's obvious you have really never used one
i also did not trust one at first but i use it now as part of a 2 step checkout
and i never miss a leak i turn on the ac and stick it the vent with ac full on.
then i place it on the floor, and then shut off the engine and insert the tip
into the drain it it leaks it will let you know
the mac one we have is the best one i have used
i used the dye to find the big leaks but it also hides leaks at the service
valves were the sniffer doesn't oh ya in this hot weatheri don't even shut off
my bench fan thats pointing at me

 

I own one, a Robinair. I know how it works and have had plenty of practice.
And years before, back in
the early 80's when the only electronic probes you ever used were in your
sex toy drawer, and before the
idiots in the auto industry figured it out, I was using electronic gas
detectors very similar in construction to
the modern ones to sniff out gas leaks in production of high voltage power
equipment.

checkout and i never miss a leak i turn on the ac and

shut off the engine and insert the tip into the drain

I told him that you have to check the evap. But the evap isn't were most of
the leaks are - or at least, not in
most other cars that don't have evaps made out of paper mache like
Chrysler's apparently are. I never heard of
an evap leaking until I bought a Chrysler. It's asinine - the evap is the
worst to remove part of the AC there is,
anyone with half a brain would have designed it with extra thick piping and
such. All the other automakers
figured this one out.

Every part of the refrigerant circuit in an A/C is a potential leak. I've
seen a leak in a 2 year old condensor
right smack in the middle of a piece of tubing. Manufacturing defect that
was - a quick bit of work with
a welding torch and that condensor has lasted for 25 years now - and this
wasn't no hairline crack, this
was a true metal flaw about the size of a pinpoint. It took a jewelers
loupe to see it and the leak was so
small that the system took 2 years to leak down to nothing. Your not going
to find that sort of thing by
jamming your probe up the condensate drain.

service valves were the sniffer doesn't

at me

Like I said, what your doing will only get the obvious ones. So your
missing the small ones and
your customers are too bonehead to understand that it isn't normal for an
A/C system to have to
be recharged every year, so they aren't coming back and jamming your probe
up your ass for
doing a half-assed job checking out their cars.


Ted

 

yea well we here are working on cars with 134 not r12 from the 80's

 

Oh yeah, I forgot that the foundrys that manufacture tubing figured out how
to
make absolutely perfect metal products with zero defects back in 1996,
me bad...NOT!!!

R134a systems are just as suceptable to leaks as R12. There is nothing in
Freon that isn't in R134a that hastens system deterioration. Vehicles
subject
the tubing and other parts of the refrigerant system to vibration, and over
time
that will shake free weaknesses. Joint seals can also fail. Flexible
refrigerant
lines have always been a problem - why do you think it is so rare to have
a refrigerant leak in something like a home refrigerator that just sits
there,
as compared to an automobile? Or a home A/C system that uses copper
braized fittings throughout except in a few places where there's large
compression
fittings? Geeze, they use the same refrigerant!

Sounds to me kind of like your working in a dealership. So, OK I can
understand -
your allotted only a few hours to make a repair and you aren't allowed to
spend the
time to really throughly check out the system. Slap it together quick and
nail down
the big leaks and let the seepers go out the door, the factory isn't paying
you to
really do a through job. Just don't be an idiot and assume that just
because you
don't have the time to do it right that what your doing is the proper way to
do things.

Sure, statistically most NEW systems won't have slow leaks since those are
more
a factor of age deterioration rather than some gross failure. So you can
get away
with ignoring most of the system. But that only means that a smaller
percentage of
seepers will go out the door on your watch - they will still be going out
the door,
though, and if you checked all of the cars going out the way you should be,
you
would catch them.

Ted

 

just so u know i'm required by law not to charge a leaking styystem and let it
leave with a charge of any sort so it does get fixed and i use dye and a sniffer
to do so
and i by far replace more evap.coils for leaks than i repair leaking lines and
just so you know r12 is r134 just in a different chemical formula

 

just so *u* know,
You're not impressing anyone with your exploits. [PREDICTION] See
assenine knee-jerk reply below. [/PREDICTION]

 

Ain't that a wonderful law? Let's see, who is required by law not to let a
leaking car out of his garage YOU ARE. Who is charged with determining
whether a car is leaking or not YOU ARE. Do you see a problem here?

How about we rewrite the speed limit laws so that the person charged with
following the speed limit - the driver - is also the person who types in the
speed limit he was travelling into the cop's radar gun. I'd go for it!!

When are you going to understand a lot of these EPA regs have no teeth
in them and are just to make the tree-huggers happy?

It's like the law mandating recovery of R134a. So, tell me, the refrigerant
industry spends years and millions developing a refrigerant that is safe
for the environment - then they pass a law saying that this safe refrigerant
can't
be released into the environment since it's unsafe?!?! Then they go ahead
and let the industry sell it in 12 ounce cans over the counter at auto parts
stores
to shadetree mechanics who do not have the expensive recovery gear?

Do you see a problem here?

Ted