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

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Steve
http://www.atlantaracing.com
Jim G - 27 Jun 2006 15:13 GMT
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.
>> What are the steps to replace the expansion valve on my 1999 GLE?
>>
[quoted text clipped - 5 lines]
> doing
> this repair.
njmodi - 27 Jun 2006 23:12 GMT
> 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.
[quoted text clipped - 20 lines]
> 10. Find a replacement expansion valve.
> 11. Reassemble and reinstall the evaporator assembly.
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
Jim G - 29 Jun 2006 01:33 GMT
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.
>> 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.
[quoted text clipped - 43 lines]
> Cheers,
> Nirav
njmodi - 30 Jun 2006 05:26 GMT
> 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.
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
Jim G - 30 Jun 2006 12:57 GMT
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.
>> I'm still waiting for the correct expansion valve. I ordered a Visteon
>> from
[quoted text clipped - 18 lines]
>
> Nirav
njmodi - 30 Jun 2006 14:40 GMT
> 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.
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
Jim G - 30 Jun 2006 23:45 GMT
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.
>> That's the first thing I tried. I put in a little refrigerant, but it
>> still
[quoted text clipped - 10 lines]
> Cheers,
> Nirav
Steve T - 01 Jul 2006 06:55 GMT
> 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.
If this system uses a suction throttle valve you better replace it as well.
It causes the same symptoms.

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Steve
http://www.atlantaracing.com
Jim G - 01 Jul 2006 17:15 GMT
STV's don't appear to have been used on the 4th Gen Maxima. I think they
were used on the '85 - '87 300ZX. Max's use TXV Thermal expansion valves.
>> 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
[quoted text clipped - 4 lines]
> well.
> It causes the same symptoms.
Steve T - 01 Jul 2006 18:37 GMT
> STV's don't appear to have been used on the 4th Gen Maxima. I think they
> were used on the '85 - '87 300ZX. Max's use TXV Thermal expansion valves.
They were used on some model maximas and Z32's as well. This valve was used
along with an expansion valve. When they stick open, they produce the
problem you described. I'm glad your model doesn't use this, guess they
went back to electrically cycling the compressor to control the evap temp?

Signature
Steve
http://www.atlantaracing.com
Jim:
With respect to the oil quantity: What the nissan service manual
recommends is to measure how much oil is left in the old compressor and
put the same amount in the new compressor. Since you have no leaks, you
should not have lost any oil, so the rest of the oil, not in the
compressor is probably in the condenser etc.
With respect to the vacuum pump. I bought a 5 cfm (probably too big)
for $160 shipped to my door, It is a Robinair 15500. You would probably
be ok with a 15150 (1.5 cfm) or 15300 (3cfm) pump. I bought it from
Washer Specialties Co. 800-835-1010. Ask for the person in charge of
internet sales. If you are anywhere near southeast FL, you can use mine.
The best two ways to charge a system are by refrigerant weight or using
the sight glass (if equipped).
I think it is very unlikely that all the components you mention were
defective all defective at the same time. What were the pressure
readings? Temperatures of the refrigerant lines? Was the problem not
related to the heater core doors stuck in the heat position? Sometimes
the receiver drier gets blocked and you will have the problem you
experienced, case in which you will see a temp difference between the
two lines connected to the drier. If the TXV closes, the compressor
readings may appear as if the compressor was defective. Most A/C
service manuals have typical pressure and temperature readings for
different system problems. I could scan and email you one if interested.
In any case, good luck.
> 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. ???
mike@ripleyhomeplace.com - 23 Jul 2006 04:46 GMT
I have a 96 GLE and the compressor just started cycling on then
switching right off again and this repeats about every 10 seconds. Some
old guy at a station in tow hooked some gauges on it and said that it
seemed liked the system was blocked. He said that since the dryer was
cheapest we should change that and if that didn't fix problem we should
replace the evaporator. Does this seem reasonable?
Mike@ripleyhomeplace.com
> Jim:
>
[quoted text clipped - 31 lines]
> > 2. Remove the blower motor assembly.
> > 3. ? Uncover the evaporator assembly. ???
AS - 23 Jul 2006 14:40 GMT
Mike:
It does not sound reasonable to me.
The reason for cycling on and off will most likely be, in my opinion,
that the system is low in refrigerant. $30 bucks spent at the autoparts
in buying the refrigerant and the charging hose should suffice to fix
your problem. The charging hose comes with instructions.
To check the dryer, just feel the temperature in both pipes that get to
the dryer itself. There should not be any noticeable temp. difference
when touching it by hand. The system would have to run for at least a
few minutes for this problem to be noticeable.
Never heard of a blocked evaporator, unless it was blocked to air
circulation (not refrigerant).
What normally blocks a system would be a defective or frozen expansion
valve or a clogged orifice.
Has the A/C system been worked on? Why would it block by itself?
Good luck
> I have a 96 GLE and the compressor just started cycling on then
> switching right off again and this repeats about every 10 seconds. Some
[quoted text clipped - 40 lines]
>>>2. Remove the blower motor assembly.
>>>3. ? Uncover the evaporator assembly. ???