Jim, Thanks for your answers. Got a little more serious about troubleshooting this last night (after installing new radiator in my Wife's Infiniti) and observed that the return line was cool but nowhere close to icing up. Airflow is not reduced after the fade-out. However, lots and lots of bubbling/surging activity at the sight glass, so it looks as if low refrigerant is the issue. :(
I've got a can of R134 with green dye, will add that and start looking for the leak(s). How many bets for/against the evaporator? -Max -----Original Message----- From: mercedes-boun...@okiebenz.com [mailto:mercedes-boun...@okiebenz.com] On Behalf Of Jim Cathey Sent: Wednesday, September 29, 2010 9:58 PM To: Mercedes Discussion List Subject: Re: [MBZ] AC diagnosis - cause of AC fade-out? > I would imagine icing inside a line > would show an unusually high high-side pressure? The icing is not inside the line, it's in the airflow path. If you have enough water inside the system to freeze, you've got a serious problem! Airflow naturally reduces when the fan speed goes down, you're looking for low flow even when on high. Compressor runs all the time, heat is added (via monovalve) to moderate the cooling. That's why "EC" exists as such. > Applying 12v makes the monovalve go to the full hot position, right? Not right. -- Jim _______________________________________ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com _______________________________________ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
