Re: [MBZ] Evap leak, was Vergasser vs. Diesel
A conversion to R134A will result in deterioration of all the seal rings in the hose fittings and compressor. These leaks are very small individual and almost impossible to detect, but in concert can bleed the system very fast. Best remedy is to remove ALL black O-ring seals and replace them with R134A resistant green ones. On 1/10/07, Trampas [EMAIL PROTECTED] wrote: Using a normal leak detector you can charge system and let sit for an hour, place detector probe near drain for evap, since Freon is heavier than air the sensor will go off. Other methods used are to place sensor in center vent and turn fan on low. This in my experiences often gives false positive readings. Also I thought I heard that the 300D and 90's W126/W124 had evaporator leaks, I am sure others here can confirm this. Trampas -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Allan Streib Sent: Wednesday, January 10, 2007 11:15 AM To: Mercedes Discussion List Subject: Re: [MBZ] Vergasser vs. Diesel, was 87 TD for sale Trampas [EMAIL PROTECTED] writes: The most common AC leak is the expansion valve, second in my opinion is the charging ports, then front compressor seals and finally evaporator. Some late models had lots of evaporator problems. My W123 300D will not hold an AC charge. Leaks down in less than a week. My mechanic put a dye in the system and could not locate the leak. He said he checked the expansion valve (it's behind the glovebox, right?) The only thing he could not get at was the evap. It was convereted to R134 by a prior owner. Does that sound like the evap is the problem, then, or could it be the expansion valve but for some reason the dye did not appear there? Allan -- 1983 300D 1966 230 ___ http://www.okiebenz.com For new parts see official list sponsor: http://www.buymbparts.com/ For used parts email [EMAIL PROTECTED] To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com ___ http://www.okiebenz.com For new parts see official list sponsor: http://www.buymbparts.com/ For used parts email [EMAIL PROTECTED] To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com -- Hans Neureiter, Houston, TX '82 300SD, '95 E300D
Re: [MBZ] Evap leak, was Vergasser vs. Diesel
I will second that -- it took three tries to get the AC working on my TE for that very reason -- the 0-rings croaked. Replace the four big ones between the compressor and hose manifold while you're at it, and the ones between hose manifold and hose set. Requires pulling the compressor, but you avoid venting it down again. You can dump the compressor oil and replace with PAG at the same time, works better. Peter
Re: [MBZ] Evap leak, was Vergasser vs. Diesel
I was sort of thinking of flushing out the whole system and converting it back to AutoFrost, or even R12. Though I know that the HC refrigerants are NOT good in a leaky system, because the individual component gasses do not bleed off at the same rate, so if you have leaks, you end up with a sub-optimal blend of gasses. Guess if the R134a has eaten the O-rings I need to replace them in any case Allan -- 1983 300D 1966 230 Peter Frederick [EMAIL PROTECTED] writes: I will second that -- it took three tries to get the AC working on my TE for that very reason -- the 0-rings croaked. Replace the four big ones between the compressor and hose manifold while you're at it, and the ones between hose manifold and hose set. Requires pulling the compressor, but you avoid venting it down again. You can dump the compressor oil and replace with PAG at the same time, works better. Peter
[MBZ] Evap leak, was Vergasser vs. Diesel
Using a normal leak detector you can charge system and let sit for an hour, place detector probe near drain for evap, since Freon is heavier than air the sensor will go off. Other methods used are to place sensor in center vent and turn fan on low. This in my experiences often gives false positive readings. Also I thought I heard that the 300D and 90's W126/W124 had evaporator leaks, I am sure others here can confirm this. Trampas -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Allan Streib Sent: Wednesday, January 10, 2007 11:15 AM To: Mercedes Discussion List Subject: Re: [MBZ] Vergasser vs. Diesel, was 87 TD for sale Trampas [EMAIL PROTECTED] writes: The most common AC leak is the expansion valve, second in my opinion is the charging ports, then front compressor seals and finally evaporator. Some late models had lots of evaporator problems. My W123 300D will not hold an AC charge. Leaks down in less than a week. My mechanic put a dye in the system and could not locate the leak. He said he checked the expansion valve (it's behind the glovebox, right?) The only thing he could not get at was the evap. It was convereted to R134 by a prior owner. Does that sound like the evap is the problem, then, or could it be the expansion valve but for some reason the dye did not appear there? Allan -- 1983 300D 1966 230 ___ http://www.okiebenz.com For new parts see official list sponsor: http://www.buymbparts.com/ For used parts email [EMAIL PROTECTED] To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] Evap leak, was Vergasser vs. Diesel
Trampas wrote: Using a normal leak detector you can charge system and let sit for an hour, place detector probe near drain for evap, since Freon is heavier than air the sensor will go off. Other methods used are to place sensor in center vent and turn fan on low. This in my experiences often gives false positive readings. Also I thought I heard that the 300D and 90's W126/W124 had evaporator leaks, I am sure others here can confirm this. Evaporator leaks were almost unheard of until the mid '80s (models 124/126). Late '80s cars and many 124/126/140s had problems with evaporator leaks until the mid '90s. They were rare in model 201s (were they were easily replaced). Marshall -- Marshall Booth Ph.D. Ass't Prof. (ret.) Univ of Pittsburgh School of Medicine [EMAIL PROTECTED]
