Author Topic: AC dripping on foot  (Read 185 times)

jtwoods4

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AC dripping on foot
« on: 05 August 2019, 11:03 AM »
Hey everyone I have a 1980 300sd in Cherry condition. Very low miles and everything works perfect. However I noticed when I'm driving around town with the AC on its constantly dripping on my foot. The foot on the accelerator pedal. what could be causing this and how can I resolve it.
1980 300SD

daantjie

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Re: AC dripping on foot
« Reply #1 on: 05 August 2019, 12:42 PM »
Check the drain tubes as a first step. They are these long rubber tubes on either side of the transmission and they end in a "fish mouth" to keep critters out. You will need a lift or jack up the front quite high for proper  inspection and clearing them out with a tool of sorts. Careful not to puncture rubber.
Also a good time to check those pesky sunroof drains  ;)
Daniel
1977 450 SEL 6.9 - Astralsilber

jtwoods4

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Re: AC dripping on foot
« Reply #2 on: 05 August 2019, 12:44 PM »
I've already put a coat hanger up the drain tube and made sure there was no dirt on your bre blocking them. Don't have a sunroof.
1980 300SD

Taha

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Re: AC dripping on foot
« Reply #3 on: 30 September 2019, 07:48 PM »
Hi,

The same thing happened to me after have the system converted to R134. It’s dripping from the expansion valve.
1978 280S

jtwoods4

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Re: AC dripping on foot
« Reply #4 on: 30 September 2019, 08:01 PM »
Yep that's it
1980 300SD

UTn_boy

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Re: AC dripping on foot
« Reply #5 on: 01 October 2019, 09:10 PM »
The expansion valve and the low pressure line coming out of the expansion valve is supposed to be wrapped in cork tape to prevent this from happening.  It has always amazed me how many I've come across that have had the cork tape removed.  You know that whoever replaced the expansion valve had to remove the original cork tape, and I have to wonder what goes through their mind when they decide that it's ok not to re wrap the expansion valve with cork tape.  Mercedes didn't put the cork tape on there for decoration. 
1966 250se coupe`, black/dark green leather
1970 600 midnight blue/parchment leather
1971 300sel 6.3, papyrus white/dark red leather
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1976 280s astral silver/blue MB Tex
1978 450sel 6.9 Euro, Anthr/velour

jtwoods4

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Re: AC dripping on foot
« Reply #6 on: 01 October 2019, 09:14 PM »
Is the expansion valve accessible without removing the dash? If so could I re-wrap it without removing the dash?

my guess is that the expansion valve was not changed when the system was converted to R34 and the original Court tape has just deteriorated.
1980 300SD

Diesel 617

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Re: AC dripping on foot
« Reply #7 on: 02 October 2019, 07:45 AM »
Pull the instrument cluster for easier access, and the foot well panels. You will see a brass box near the evaporator box. Wrap that box up and the lines as best you can.
X3 1980 300SD Blown Heads, trans -Retired
1980 450SEL Parted out
1980 450SEL to Diesel Parted Out
1979 280SE Euro Spec Cloth Seats: Needs Rebuilt head and WUR
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Taha

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Re: AC dripping on foot
« Reply #8 on: 07 October 2019, 12:09 PM »
Is the expansion valve accessible without removing the dash? If so could I re-wrap it without removing the dash?

my guess is that the expansion valve was not changed when the system was converted to R34 and the original Court tape has just deteriorated.

As Diesel 617 said you just need to remove the instrument cluster and the below panels. Mine is original and I prefer to stick whit it as the r134 compatible aftermarkets are not reliable in my idea.

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1978 280S

jtwoods4

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Re: AC dripping on foot
« Reply #9 on: 07 October 2019, 12:11 PM »
Awesome thank you guys.
1980 300SD

daantjie

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Re: AC dripping on foot
« Reply #10 on: 07 October 2019, 12:54 PM »
I used 3M Strip Calk on mine. I'm sure purists will disagree but it works like a charm ;D
Daniel
1977 450 SEL 6.9 - Astralsilber