W123 240D A/C Condensation Evacuation Tube Not Working - PeachParts Mercedes-Benz Forum

teddyd49 · #1 05-01-2015, 08:07 AM

Have a 1982 240D Sedan w/Manual Transmission and full A/C unit that is working properly except for one item. Have noticed that there is no pooling of water underneath this car when engine is turned off and it is parked. There appears to be NO release of condensation from A/C unit through the tube intended for this purpose. Have fully cleared this tube of years of build up from hardened algae et al yet it still is not releasing any condensation from A/C usage.

Have had a lingering leakage problem with water coming into passenger cabin from outside during heavy rain storms. Have fully replaced floor boards in car, replaced weather stripping/seals on doors to minimize water leakage. Yet it now appears that the condensation from A/C unit is slowly leaking back into cabin of car from a/c-heater box mounted behind middle console under the dash rather than through the tube intended for this purpose.
This car is not leaking any anti-freeze.
Is there some kind of sealed vacuum valve underneath the a/c-heater box or a torn/aging gasket around a bolt that might be causing this leakage?
Any thoughts on how to FIX this problem or has anyone experienced a similar phenomenon with their W123 sedan?

vstech · #2 05-01-2015, 08:29 AM

Search for foam tube.

Under the dash there is a foam tube that fails. There is one on each side of the evaporator box I think, but search the forum for the info.

Lots of threads on fixing it.
If it's gone or torn, the condensation will fill the rear floorboards with water...

jay_bob · #3 05-01-2015, 08:14 PM

The drain on a 240D is on the driver side on top of the transmission. There is a spout on the air box that drains through the foam tube through an opening in the floor pan onto the top of the bell housing.

A 16-ounce soda bottle neck makes a decent temporary funnel to redirect the water out of the car. Use a soda bottle, those are nice thick plastic since they have to hold the pressure of the soda. Water bottle plastic, since there is no pressure, has gotten paper thin.

I would pull up the floor mats and under padding behind the front seats and inspect for water accumulation. It will soak into the pinch welds and cause them to rust out. BTDT.