What are the steps to replace the expansion valve on my 1999 GLE?

1. Remove glove box.
2. Remove the blower motor assembly.
3. ? Uncover the evaporator assembly. ???

Jim G wrote:


Remove the evap assembly and disassemble. Also replace the drier while doing
this repair.
--

Steve

http://www.atlantaracing.com

I just removed the evaporator assembly. Here's how I did it. I'll post a
link to a write up with pictures in the next couple of weeks.

1. Remove glove box. There are four screws in the corners of the glove box
assembly. There are also two screws that hold the latch retainer at the top
of the assembly. Pull out the glove box assembly. Disconnect the two wiring
harnesses.
2. Remove the horizontal metal support brace that runs across the bottom of
where the glove box hangs. There are four screws.
3. Evacuate the A/C system. You could do this first. All the pressure must
be relieved prior to opening the system.
4. Disconnect the high and low pressure sides in the engine compartment at
the firewall. These are the connectors for the evaporator.
5. Remove the four large screws that hold the evaporator assembly to the
firewall.
6. Pull out the evaporator assembly.
7. Disassemble the evaporator assembly by removing the screws and one clamp
that hold the two housing sections together.
8. Remove the evaporator and the attached expansion valve from the plastic
housing.
9. Carefully disconnect the three nuts that connect the expansion valve to
the evaporator.
10. Find a replacement expansion valve.
11. Reassemble and reinstall the evaporator assembly.

"Steve T" <fotocord (AT) yahoo (DOT) com> wrote

Jim G wrote:
Jim - great write-up. A few follow-up questions:

0. What were the symptoms that led you to diagnosing the expansion
valve as the problem?
1. How did you evacuate the AC system?
2. How did you make sure that when you reassembled the evaporator
assembly, valve and reattached it to the high and low lines, how did
you make sure there was no leak before you recharged the system?
3. Did you recharge the system yourself after you were done? (If yes,
how did you do this accurately).

Cheers,
Nirav

I'm still waiting for the correct expansion valve. I ordered a Visteon from
partsamerica.com. Hopefully this one is the same as the one I removed. I'm
not sure the expansion valve is the problem. I'm replacing it along with the
compressor and the drier. My single symptom was that it blew warm. My local
dealer tested the system and found no leak. Their suggestion was replacing
those three items and recharging the system. At first, I ordered the wrong
compressor and drier. Finally figured out the 01/99 Max has basically a 2000
A/C system. Now I have the correct compressor and drier (partsamerica.com).
I also have new O rings.

I ordered some Nissan PAG oil, although I have no idea how much to pour into
the compressor. The label on the inside of the hood says the oil charge
should be 8.5 fluid ounces. Does my Calsonic compressor require 46 viscosity
oil? No one seems to know, not even the dealer. There must be some residual
oil still in the lines. I may pour three or four ounces in the new
compressor. Does evacuation remove any oil?

My plan is to reassemble the system and evacuate it with an electric vacuum
pump (that I don't know where I'm going to find). I understand that I should
hold the vacuum at 29.5 inches of mercury for 30 minutes to several hours to
ensure that moisture in the system boils away. Then I plan to put in
approximately 24 ounces of R134a (1.43 plus or minus .11 lbs). My son is ASE
certified and has a manifold. I'm not going to be interested in the high and
low side pressure.

The compressor did not have a catastrophic failure, so I hope the evaporator
and condenser are not overly contaminated.

Hopefully there's no leak. My fingers will be crossed. If all this fails, I
guess I'll have to start replacing more pieces of the system.

"njmodi" <njmodi2 (AT) yahoo (DOT) com> wrote

Jim G wrote:
Great write-up - thanks for the details.

Not to ask the obvious, but did you check to see if there was the right
amount of refrigerant in the system? I mean if there were no leaks,
you might have just been low on refrigerant. I would think that a
competent AC shop could have given you a better diagnosis than "replace
all the parts"... just my 2cents... I'd hate to take on all that work
as a crapshoot.

Good luck with it!

Nirav

That's the first thing I tried. I put in a little refrigerant, but it still
blew warm. I'm looking for a decent vacuum pump. I see there are a few on
eBay. I have a feeling I will have to evacuate the system several times
before I get it all working.

"njmodi" <njmodi2 (AT) yahoo (DOT) com> wrote

Jim G wrote:
Jim - it takes a very specific amount of refrigerant for the AC system
to work properly. IMHO, the first thing you should do is go to a local
shop that specialized in AC repair and have them just evacuate/recharge
the system. It should cost less than a 100 bucks, it's all automated
and they'll probably double check for leaks before charging it.

Cheers,
Nirav

I already have the system disassembled and am waiting for the expansion
valve to arrive. I'm also waiting for the Nissan PAG oil. I may buy a vacuum
pump. They're not too expensive. That way I can evacuate the system...and do
it right the first time.

I plan to put in two twelve ounce cans of refrigerant. That should put me
right on the money. Still got my fingers crossed.

"njmodi" <njmodi2 (AT) yahoo (DOT) com> wrote

Jim G wrote:


If this system uses a suction throttle valve you better replace it as well.
It causes the same symptoms.

--

Steve

http://www.atlantaracing.com