I just recently bought my first Mercedes (my wifes). I have never worked on Mercedes before, but a/c works great while we going down the road, I mean good cold air, but as soon as stop and sit still for a little bit, a/c stops working. I am mechanicaly inclined but I have no idea where to sart on this. Please help, (wife not real happy) . This is a 1995 E420

Going down the road, air goes across the condensor, removing the heat from the system (not going to explain the entire ac process here).

Stopped, you MUST have the electric fans working to remove the heat. Start there.

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1990 300CE. Garage kept all its life. Looks & Runs Like New. Everything works. White w/Palomino int. Pioneer 12 CD player in the boot. 17" Enkei LX-F Chrome wheels w/Falken Azenis ST-115 225-45 tires. Tinted windows. Black sports grill w/Euro clear front lamps.

I have already checked the electric fans on the front they are both working.

ok now you need to check the engine fan clutch.with car warmed up and idling and a/c on take a shop rag or towel and gently touch the inside[engine] of the fan blade and see if you can stop it.if you can it's new fan clutch time.

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David S Poole
European Performance
Dallas, TX
4696880422

"Fortune favors the prepared mind"
1987 Mercedes Benz 420SEL
1988 Mercedes Benz 300TE (With new evaporator)
2000 Mercedes Benz C280
http://www.w108.org/gallery/albums/A...1159.thumb.jpg

Also ensure that the airway is clean.

I noticed the other day that clutch fan was not turning very fast, and yes I can stop it by hand . Thanks for info. . I figured that the electric fans would make up the differance, and was not sure how fast the clutch fan was suppose to turn either. Again thanks for the help. I will replace the clutch fan as soon as I can. Parts are not cheap for Mercedes.

Also make sure that your system is giving you 100% recirc air when interior is initially hot on startup or as demanded by the recirc switch on the front panel. My '92 300E has one or both recirc valve which has a leak and will not give me 100% recirc air no matter what. Only 80% recirc air. I am going to pull the dash next week and replace these valves along with some other vacuum valves in the A/C system. You can check by pushing the recirc swtich up and getting the red light, then go outside where the air enters the A/C system at the back of the hood and feel for air draw or use a piece of paper. If there is any air draw at all, one or both of the A/C recirc valves has a leak on the high draw(100%) side.

What you describe is normal. There is never 100% recirc unless you modify the system.

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08 W251 R350
97 W210 E320
91 W124 300E
86 W126 560SEL
85 W126 380SE Silver
85 W126 380SE Cranberry
79 W123 250
78 W123 280E
75 W114 280

I replaced mine on my 92. The part is very expensive, not bad to remove, but very little room in the front. You might consider remove the radiator to give yourself more room.

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93 Toyota Corolla 177K
95 S 500 coupe 82K
92 400E 180K (SOLD)
94 E 420 150, blown gaskets (SOLD)
http://www.kanio.net/mercedes_signature.jpg

DEFINITELY remove the radiator to do that job, it makes it far easier. Brace yourself for the cost of that part - it is far out of line from the lack of complication on that piece of equipment. :-(

Thanks for all the help. I sure did not realize that parts were that expensive for a mercedes. It might be awhile before can replace fan clutch. Is it possible to put a straight fan on, and everything work ok? I got a great deal on this car only paid 1500.00 for it and it is in good shape. Has some minor problems (paint faded on roof, head liner loose) other than that it's alright. Just going have to get second job to buy parts.

There is another path that you could pursue. People have fixed these clutches by replacing the oil. Include "Toyota" in the search string, as they sell the oil.

Do they work at both speeds?

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It is a truism that almost any sect, cult, or religion will legislate its creed into law if it acquires the political power to do so. Robert A. Heinlein


09 Jetta TDI
1985 300D

1984 300d turbo 147k
your a/c gas is low, take it to a a/c shop, they added 2 lbs r12 to
my a/c, now cold a/c

Wow. I was wondering if I was just getting numb to MB part prices. While I was at ********' site, I looked up a new fan clutch for my w202 and while $97ish isn't cheap, it is not bad for an MB part. I wondered why you were so shocked. I then looked up the price for your E420 and now see what you are talking about @ $600ish!