Leaking AC from expansion valve

1994 TOYOTA CAMRY
110,000 MILES • 6 CYL • 2WD • AUTOMATIC
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JBECK2862
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I just recently replaced the expansion valve and o-rings. Pulled a vacuum and let it sit for a few minutes and the vacuum did not hold. I did notice that the expansion tubes are loose and will not tighten against the expansion valve. Am I doing something wrong? Do I need to replace the tubes? Should I have unbolted the tubes from the two nuts inside the firewall or the two bolts outside the firewall. I could not see an easy way to take off the outside bolts behind the engine as they are blocked.
Aug 3, 2018 at 8:27 PM
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JACOBANDNICKOLAS
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Hi and thanks for using 2CarPros.com.

What I have are the directions for removal and replacement of the expansion valve right from alldata. Take a look through the specifics to see if you did it correctly. The attached pictures correlate with these directions.

REMOVAL AND INSTALLATION
1. Disarm airbag system as outlined under Airbags and Seatbelts.
2. Recover refrigerant.
3. Remove blower unit, as follows:
a. Remove glove compartment.
b. Disconnect ECU electrical connector, then remove ECU and bracket.
c. Disconnect connector bracket electrical connector, then remove connector bracket.
d. Disconnect blower unit electrical connector.
e. Disconnect air inlet damper control cable.
f. Remove blower unit three attaching screws and nut, then remove blower unit.
4. Disconnect and cap evaporator liquid and suction tubes.
Removing Evaporator Case Cover
Removing Evaporator Core
Removing Expansion Valve
5. Remove evaporator cover.
6. Remove evaporator assembly, then separate evaporator and expansion tube.
7. Reverse procedure to install.
8. When new evaporator is installed, add 1.6 oz. refrigeration oil.

TORQUE VALUES
Expansion Valve To Evaporator: 4.8 lb.ft. (5.4 Nm)
Refrigerant Tubes: 7 lb.ft. (9.8 Nm)

I hope this information is helpful. Let me know if you have other questions or need additional help.

Take care,
Joe
Aug 3, 2018 at 9:03 PM
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JBECK2862
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These are exactly the steps I already took. The only thing I did not do is torque the bolts just tightened them by hand. There is still air leaking from where the expansion tubes meet the expansion valve. Is it possible I over tightened the bolts? Why would there still be a leak?
Aug 3, 2018 at 9:52 PM
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JACOBANDNICKOLAS
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I would suspect that an o-ring was damaged.
Aug 3, 2018 at 10:05 PM
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JBECK2862
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Update: I was able to get the expansion tubes to seal against the expansion valve. What I did was put two o-rings behind the expansion tube between the tubes and the plastic block that holds the nuts for the bolts. After putting it back together and pulling a vacuum it held the vacuum for over an hour. I will now attempt to recharge and see what happens.
Aug 4, 2018 at 8:41 AM
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STRAILER
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Nice work. I am thinking the new expansion block must be a little different depth wise. Here is a guide to help you vacuum down and recharge the system:

https://www.2carpros.com/articles/re-charge-an-air-conditioner-system

Please let us know what happens.

Cheers, Ken

Aug 6, 2018 at 3:26 PM