View Single Post
Old 08-17-2016, 03:33 PM
DeliveryValve's Avatar
DeliveryValve DeliveryValve is offline
Chairman of my Benz
Join Date: Jun 2006
Location: Central California
Posts: 4,105
Originally Posted by Demothen View Post

The new Evaporator (Part 123-830-14-58) is very similar in dimensions to the old evaporator (Part number not known), except that the port location is slightly different, and it is roughly 1/2" thicker in one dimension. It seems to fit the Behr housing, except for one area near the ports where the fins are interfering with the housing, which would require a small area to be cut out and new plastic to be added to enclose the part. I've drawn a rough idea of the area that would need to be trimmed on the housing in gold marker. I suspect the parts (not shown) that capture the tubing to the input/output ports would need modification, although that was primarily sealed with some sort mastic or similar sealant.

My biggest concern with making these modifications is ensuring that there's adequate and even airflow around the evaporator. The new evaporator is slightly larger, which should help with cooling capability, but I'm not able to model the airflow to ensure that it flows evenly through all parts of the evaporator.
On that evaporator it is actually 1/2" longer that the air flow has to go through, which mean more cooling fin contact area. That evaporator is one of the largest I've seen comparing to other makes and models. Which are usually much smaller.

On another note, here are some pictures of the Siemens evaporator box in three pieces with my old evap with deteriorated fins.

Attached Thumbnails
'85 w123 Complete AC system rebuild-siemenshousing1.jpg   '85 w123 Complete AC system rebuild-siemenshousing2.jpg   '85 w123 Complete AC system rebuild-siemenshousing3.jpg   '85 w123 Complete AC system rebuild-siemenshousing4.jpg   '85 w123 Complete AC system rebuild-siemenshousing5.jpg  

1983 123.133 California
- GreaseCar Veg System

Reply With Quote