1977 280z AC -- issue # xx of yy

[ess1]

Dave, I stumbled over your idea to "gut the original valve" and use it as a manifold. I will follow up with more pictures when it is finished. Best Regards from Norway.

[Dave WM]

nice work! that would be great if it works out for all those searching for a good expansion valve. Looking forward to progress report. 

[ess1]

Hi,

The manifold for the new valve is mostly finished, I have not removed the "inboard end" just in case it will need more machining. I will also have to make a steel plate similar to the "flange" on the original valve. This loose plate will enable the manifold to be rotated, to orientate the inlet of the new valve in the desired direction. I decided to make a hose connection so that I can use the manifold also for the flushing of the evap. The first flushing adapter, as shown in the picture in the post above, was made from 40mm Al, which is to small (you can see the O-ring). The new manifold is made from 50mm Al. It is winter now so this project will be on hold until....later. I have ordered an elbow just to line up the inlet to the new valve, not sure if it will fit. The alternative will be to just make a hose from the  connection in front of the Fire Wall to the new valve. 

[Dave WM]

looking good!

[ess1]

Update. Flushed Evaporator with Alkylate gasoline (-for lawn movers etc.), this fluid i mineral and evaporates easily. I don't smoke. Hose inlet connected to R12 inlet on evaporator, hose out in front of Fire Wall (suction). Test fitted all hard ware, did not have to cut the inlet pipe, just loosened the clamp where pipes enter evaporator box and adjusted the pipe by hand. Pictures in the attached pdf. Erling.

flushing and parts mockup.pdf

[ess1]

[Dave WM]

wow that is some really nice work you have there!

[ess1]

Done, it worked. I assembled the whole proses in the attached pdf. I need a new condenser, but that is on the outside of the car, not inside the dash.

Brgds Erling Søvik, Norway.

Flushing and parts mockup_ Final installation and testing.pdf

[Dave WM]

nice job, great write up! thanks for sharing!!

[240zadmire]

Very nicely done.  I won’t be able to do this as I don’t have a lathe 😞 perhaps next Father’s Day wish list and the wife agree 😉

 

as did my stock setup, I manage to just simply retro the r134a fittings.  The condenser and compressor works for a year and last weekend was blowing hot air.  Appeared all Freon escaped.  Pull the vacuum for 40 minutes and seem like there isn’t a y leak anywhere.  Put another 2 cans, (18oz or so) it’s running cool again.  Did put some dye in and even stay soap every connectors.  All seem good.  If any leak, probably in the condenser under the dashboard.  Pain in the behind 

[cgsheen1]

There are only 2 flare connections and the large o-ring that seals the expansion valve inside the dash. They're fairly easy to access and soap since they're right in front of the evaporator. Although not impossible, I would highly doubt a leak on the evaporator itself. My bet would be that your leak is probably the compressor.

Another tip about "soaping" joints: It's actually better to test with low pressure. Sometimes high pressure will just blow the leak locator solution away from the joint so quickly that you won't actually see it. In that case it's better to use a more viscous locator solution. In this case just go slowly and make sure the solution envelopes the fitting and you're checking all angles. You can locate leaks in piping with 1/2 PSI. Few people know this but the natural gas piping to a residence comes into the home at 1/2 PSI. We test the natural gas piping to 10 PSI for 30 minutes, but you can see a leak bubbling the leak locator at 1/2 PSI.

Edited June 20, 2022 by cgsheen1

[240zadmire]

will try your suggestion.  California is getting sizzling.  Not to the point of boiling eggs on the asphalt, but getting there.