A question on recharging the AC? Thanks!

Hi,



I just got me a 2002 Concorde. The AC is not working on it and after
checking it out I noticed that there was a leak on the suction line. The
rubber part of the suction line is punctured right in the middle. It is
rather a big gap; it looks like someone did a job on it with a knife or a
screwdriver! Don't ask me why. My friend checked it out yesterday and he
said that it is totally empty. Today, I got the suction line from the dealer
for $40 and we are going to install it in the morning.



I just have a couple of question for you, hope someone can help out! I read
in the book that this system has 5 OZ of PEG oil in it, so how much do I
need to have my friend put in it when he charges the system tomorrow? I am
assuming that it does not need the full 5 OZ because some of the oil is
still trapped in there! The other question, should I have my friend do the
job for me? It is straight forward and he got the machine in the shop where
he works and we got the OK to use it tomorrow. It is going to cost me about
$30 to do it this way instead of going to the dealer and shelling out ~
$200!



Thanks,

M.

 

Your troubles and costs are probably just beginning.

If we all lived in a perfect world, the hole in your suction line would have
appeared
the day before you bought the car, and there would be nothing else wrong in
the
system, your friend would charge it and off you go.

But in reality the system has probably been open for years, the
accumulator/drier is
saturated with water, and as soon as you fire it up the water in the system
will instantly
turn to ice that will jam your compressor solid, bending all it's valves and
destroying
the compressor clutch. That is, if your lucky enough for the hole in the
suction line
to be the ONLY hole, and the refrigerant doesen't come rushing out some
other hole
as fast as you put it in.

If this was my car I would do the following: Install the hose, pressure
test the system,
repair any other holes, pressure test the system again until I knew it
wasn't leaking,
remove and replace the accumulator/dryer, pull vacuum on the system for
at least 4-6 hours, put in about 2 oz of oil, and charge the system and
cross my
fingers that the original reason the system died wasn't a blown up
compressor.

And if it worked, I'd count myself lucky if I got 5 years of life out of the
compressor.

If te compressor blew I'd then completely disassemble the system, flush all
lines,
replace the compressor, expansion orifice, accumulator, all o rings, and
repeat the above
steps, excepting adding in the correct amount of oil.

At least you got one thing right - you aren't shelling out $200 to the
dealer. Why - because
$200 wouldn't pay a quarter of the cost to do this system up properly so
that it doesen't
blow chunks 30 days afterwards.

Ted

 

Because we are on A/C, if I may piggy back here. Will a properly charged
system take less engine power and produce less heat?

Just questioning because my van started to show signs of less than
efficient running. When at speed it is fine but when sitting at a light
it does not cool very well.

Thanks,
Fred

 

yes. don't know about heat production, but a system too low will not cool
so well, as a result you crank up the ac, so it runs longer.

when sitting at a light the airflow through the condensor is lower, the
condensor cannot give up as much heat.

before suspecting the refrigerant level, make sure that if you have a
electric fan that it is running when your at idle with a/c switched on, make
sure the ac condensor fins aren't clogged with dirt/dust/leaves.

Ted

 

Thanks Ted.

No electric fan, it is a thermostatic clutched fan. I was thinking about
putting an electric fan on this vehicle though. I use it to pull a
camper with and I thought replacing the clutched fan with an electric
would reduce engine drag, increase performance, and as a result reduce
engine heat.

Thanks again.

 

You do realize that you would be trading a mechanical load for a
just-as-real electrical load on the alternator, which translates back
into a real mechanical load on the engine with the conversion
ineffeiciency of the alternator added in?

However, I do not know what the overall efficiency of the clutch driven
fan vs. electrically driven fan is - there may in fact be an overall
gain. Point being it's not a total shedding of load, the net being the
difference between the two methods of driving the fan - and I'm not sure
which is the larger load on the engine.

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

 

Many people don't realise this. I did, by the way, find your power input
vs. alternator output graph; do you still need it?

 

Absolutely - thanks! Any particluar alternator? The thread I needed it
for has been dead for a few weeks, but I might still post it there to
finish it out. But I would like it for future reference.

If you don't still have my e-mail address, I'll send you an e-mail for
you to reply to.

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

 

Same one (original Chrysler unit) for which I posted the graph that didn't
have what you wanted. I'll need to go get it scanned; it's from an
astoundingly exhaustive UK MIRA test of a 1961 Valiant. They didn't just
road test it, they also dust-tested it, water-tested it, brake-tested it,
dyno-tested it, cold- and hot-soak tested it, and disassembled it down to
the last screw and nut to analyze each and every part.

Of course I still have it -- what if you need more oddball bulbs?!

 

....and what it knows, you ain't had _time_ to learn...

 

Yes, I understand the trade there. However, in my feeble mind I could
not imagine the electrical load resulting in as much mechanical load as
the engine driven fan.

 

if you're going to be pulling a trailer, stick with a mechanical fan.
they just plain move waaay more air for the $$. be prepared to spend
around $400 for a strong enough electric setup to replace a mech.
clutch fan.

-Bret

 

Of course!

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

 

interesting thoughts.

I have not experience any heat problems this year, but last year I was
tow this camper up a LONG gradual hill and when the temp got up there
and the clutch kicked in I noticed a lot of lost power and a momentary
temperature spike. Scared me because this is a new engine and the tranny
was rebuilt about 3 years ago.

 

the loss of power is because the mechanical fan is moving ALOT of air.
can't answer to the temp spike, might need a new radiator like my
chevy K2500 did. (only got hot in the mountains on I68 in MD and W
VA). if it's not cooling sufficiently, try a new $40 fan clutch
before the $400 electric setup.

-Bret

 

Got it.

You all have been great! Thanks for the input.

 

What?

 

Are you ready boots!? Start walkin'
Da da da DA! (boom) Da da da DA! (boom)

That was pretty obscure, Stern, but I got it first time I read it.
We're showin' our age.

You keep lying, when you oughta be truthin'
and you keep losin' when you oughta not bet.
You keep samin' when you oughta be changin'.
Now what's right is right, but you ain't been right yet.

Ah they just don't write 'em like that anymore! Truthin' and samin'.

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

 

See Bill Putney's response; he got it.

 

Eh? Speak up, I can't hear ya when ya mumble! Where's my damn ear trumpet?

It's true -- they don't.