'90 LS400 - R12 to R134 A/C Conversion

'90 LS400 240,000miles
With no A/C blowing, I recently converted the refrigerant from R12 to R134. The system still does not blow cold. Dealership says compressor
is gone. Worked fine in the fall. While investigating rebuilt OEM compessors, I read some posts re: the upgraded R134 system working at different pressure than the R12 system and the original A/C pressure valve (which controls the compressor) may not work when the system is converted to R134.
Any merit to this? Should the original pressure switch work properly in a converted A/C system?
Thx Chip L
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

The process of converting from R-12 tro R-134A is more than just filling the system with 134-A. Besides evacuating the system and draining all of the old oil, you need to replace the receiver-drier.
Here is a pretty thorough description of the process: http://www.dmcnews.com/Techsection/r134.html
--

Ray O
(correct punctuation to reply)
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

and of course any rubber bits in the system. A drop in replacement gas would be an easier way to go.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Site Timeline

Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here. All logos and trade names are the property of their respective owners.