Expansion valve replacement procedure

[Roa, Greg]

I just thought I'd relate some information that I learned last night, and give some answers to a question that David Ullrich asked a couple of weeks ago.

The A/C expansion valve in a 4kq, and later coupes, does not take 30 minutes to replace.

I will also give a guide on how to replace an expansion valve in one of these cars.

Step 1.  Drive to a mechanic who you don't care for much.
Step 2.  Tell him what you want replaced, hand him money.
Step 3.  Walk to a bar, far enough from the shop that you won't hear him screaming, have beer.
Step 4.  Go back, pick up car, go home, with new expansion valve.

If you really want to do it yourself, procedure is as follows.
Est. time 2-3 hours.
Est. difficulty 9 (1 is opening hood, 10 is clutch on 4kq)

Make sure A/C system has no pressure.
1. Remove glove box from car.
2. Remove flimsy plastic cover from over wiper motor/blower cover area.
3. Remove blower cover (has 4 screws holding it in), and loosen screws that hold in evaporator.
4. Loosen the two main fittings holding in the expansion valve (access from where glove box was) and remove from valve.
5. Follow two  very small diameter copper tubes leading from expansion valve.
6. Notice that they run around to the front of the evaporator, and sigh.
7. Pull evaporator back and down, so the front side is visible from the cutout below the blower cover. (will require loosening drip tray, and pulling out of place)
8. Fit wrench in through cutout, and loosen up fitting that connects tube from expansion valve to evaporator pipe.
9. Cut black goopy crap on evaporator pipe back, to expose as much of the other copper tube as possible.
10. Pull out expansion valve, cutting 2nd tube if you can't get it fully exposed.
11. Route little tubes for new expansion valve to the same place as the other.
12. Stick the tube with the closed off end to the evaporator pipe, and secure into place with black goop. (This tube just sits on the pipe, no fittings)
13. Put new o-ring on the fitting at the end of the other copper tube leading from the expansion valve, and screw onto evaporator pipe.
14. Maneuver evaporator back into place.
15. Reinstall everything else, using new o-rings on the expansion valve's other two fittings.

The worst part about this job, is that steps 8-13 all must be done through the cutout under the blower cover, which is not large enough to fit two hands through, is sharp on the edges, and generally becomes a pain in the butt.

In response to David Ullrich's question a few weeks ago, on whether the 3 hours charged by his mechanic to replace the valve was fair, I say yes.  It may not have taken him three hours, (mine took at least this long, but I was figuring it out as I went, as there is no documentation in the Bentley) but the aggravation that you save is well worth it.

For the record, my expansion valve appeared to be fine, but then again, I don't know if it was for sure, and I wanted to replace the o-rings anyhow.

Good Luck!
Greg Roa
Cincinnati, OH
86' 4kcsq
93' 90 CS
83' 944