Ok all, since this is in the heat of summer, I got sick and tired of sweltering in the heat. I just finished up a great pictorial on overhauling the A/C system with LOTS of pics! I cover expansion valve replacement, compressor and drier removal and install, proper flushing and everything in between.

And...I got the air to blow 38 degrees at the vent on almost a 90 degree day with high humidity.

YOU can fix it yourself, so get out and do it!

Let me know if this helps anyone and suggest other items I can do a pictorial on.
When you get on the page scroll down to neat the bottom of the page.

http://dieselgiant.com/mercedes_diesel_maintenance_tips.htm

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1981 300D 147k
1998 VW Jetta Tdi 320k
2001 Dodge Ram 2500 141k
1979 300D 234k (sold)
1984 300D "Astor" 262k(sold)
Mercedes How-To and Repair Pictorials
I love the smell of diesel smoke in my hair

I just saw it in the other thread, well done!

Stuff I need to tackle soon, I'm seeing how hardcore I am before I really need AC in Klaus... it's only been in the low 90s and I can take that but the upper 90s/low 100s are looming so I must act here pretty quick.

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I'm not a doctor, but I'll have a look.

'85 300SD 245k
'87 300SDL 251k
'90 300SEL 326k

Six others from BMW, GM, and Ford.

Liberty will not descend to a people; a people must raise themselves to liberty.[/IMG]

I guess I am missing something, I couldn't find anything to do with AC on that site.

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1977 300D Lost coolant while someone else was driving
1983 300D Can't run without oil
1985 300SD (gone but not forgotten)
1990 300TE 4matic Sold
1991 Yamaha Venture
1975 Kawsaki 250 triple
1974 Honda 200CL
1951 8N Ford
2008 Wildfire 650C

It is there....down lower on the page..

After the part about fixing the odometer?

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1977 300D Lost coolant while someone else was driving
1983 300D Can't run without oil
1985 300SD (gone but not forgotten)
1990 300TE 4matic Sold
1991 Yamaha Venture
1975 Kawsaki 250 triple
1974 Honda 200CL
1951 8N Ford
2008 Wildfire 650C

Yes you will have to scroll down toward the bottom of the page. I don't know how to put an index at the top of the page that is clickable, so it transports you to the right spot.

__________________
1981 300D 147k
1998 VW Jetta Tdi 320k
2001 Dodge Ram 2500 141k
1979 300D 234k (sold)
1984 300D "Astor" 262k(sold)
Mercedes How-To and Repair Pictorials
I love the smell of diesel smoke in my hair

Thanks, we can use the help

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2000 Ford 7.3 Powerstroke 4x4
2006 Mazda Tribute
1983 Black 300 D (donated to charity)
1993 Teal 300 D (160K) Sold
"I love the smell of burnt diesel fuel in the morning, it smells like ....VICTORY"

Semper Fidelis
USMC 1973-1976

My 1982 300sd air cond. got fixed today. I put in a new accumulator/dryer and a push button control unit and had the dealer evac and recharge. I drove the hour home (50 miles) with the air full blast and coldest setting. When I got home, my hands were numb from cold and I had chill bumps. No kidding. I think it's colder than 38 degrees. It was 98 degrees outside here today with 98% humidity.

How about that for cold. Sorry I could not do it myself. I didn't have the evac equipment or a way to borrow it.

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1982 300SD Light Blue
2002 Honda Accord SE
1974 Toro Wheel Horse Tractor
2000 Toyota Tundra Pickup

willrev,

When it comes to summertime in the heat, it doesn't matter if you do it yourself or not. A/C has gotten to be mandatory equipment these days.

You can get a dial thermometer for about $5 at that auto supply. Put one in the vent and see what the vent temp is. I don't know what model you have, but if it is an MB with climate control, it is most likely 38 degrees or so. The climate control system won't let it get lower than that to prevent evaporator freeze up.

Stay cool,

Brian,

You are so right. In addition to what you said, often people will offer as a the solution whatever they found to be the problem on their own car if the symptoms were even remotely similar. As you say this isn't precise, but in their own way, they're just trying to help.

What can be a problem for the person asking the question is when the person offering the answer words it in such a way as to make the person think that their experience is just the only possible solution.

It's hard for us all on mshop to keep the wheat separated from the chaff.

Have a great day,

Come now dont be scared of freeze 12. Even the precious diesel you fill up with everyday is a "blend".

Well for that matter R-12 is a blend.

The proof is in the vent so to speak.

I tell you all what. Since everyone is SO worried about me using Freeze 12 in the old benz. If someone one will send me 2.6lbs of R-12 I will be gald to properly recycle the Freeze back into its 30lb container and charge-r-up with ole R-12. I am being serious. If you have 3 1lb cans and deem that it is that serious, and you loose sleep over it, I will gladly take your R-12 and install it.

Now we will see how important it is to the "watchdogs" if they send me the R-12.

__________________
1981 300D 147k
1998 VW Jetta Tdi 320k
2001 Dodge Ram 2500 141k
1979 300D 234k (sold)
1984 300D "Astor" 262k(sold)
Mercedes How-To and Repair Pictorials
I love the smell of diesel smoke in my hair

Honestly, I don't believe the "watchdogs" give a $hit what is in your system. In fact they are probably perfectly fine with it because the system is performing exactly as it was designed to perform.

The concern is simply the future addition of Freeze-12 and/or the evacuation of the fluid if and when you need new parts in the system.

Nobody can argue with your individual success. The 38° vent temperature confirms this.

We have said before you can do what you want with your car...

What is at stake is the advise to people who may not know that there are other considerations... That is why Larry and I stay in the fight...

If you want R12 it is easy to get on Ebay... that is where I got the 7 cans I own...

I have never seen anyone who could mix up so many concepts in one thread.

So, what happened to your "134 is toxic" argument?

BTW, Brian is right in saying that we are glad that your system is running cold.

Have a great day,

I hope this post doesn't get lost in the middle of this great conversation, but it seems like one of the best places to post.
My '82 240D has the R134 AC system and I have added freon recently.

The problem is, when I drive in town, about 20 to 30 minutes into the drive - this is with stop lights and traffic, but not stop and go rush hour traffic - the AC stops blowing cold air. It starts to lose its punch and then dies. I still get air from the fan, just nothing cold. It will actually blow hot air on a hot day. Adding freon does not fix it. If I park for 30 minutes with the engine off, it will blow cold again.

Any ideas what could cause this? I don't want to jump into re-building the whole system if it is a far simpler issue.

I believe (and will have to look it up in my records) that the AC system was worked on by a mechanic about 5 years ago. This could have been my other car though, I cannot remember off the top of my head.

Thanks for any help.