He added freon, worked for five days, then didn't.
Any chance theres a freon leak?
What are his reasonings behind changing the compressor?

Please update your User CP so we know what vehicle your speaking about for a start

 

Ac problem

I am talking about ML320 2000, Frion is full still, no leaks.
He says next step is the compressor.

 

I am talking about ML320 2000, Frion is full still, no leaks.
He says next step is the compressor.

The cheapest is to get a used one on ebay but with those things even thoug they are in good working condition the problem is u dont know how long they may last. Or get a remanufactered one which is more expensive than the used ones.

 

From 1998 to 2002 the 320s all used the same Denso compressor.
Here is a brand new Denso for $270. it is not a rebuild. It is on Amazon.
I have gotten one there and an alternator for my E500. If you do not like
Amazon then partsgeek.com has it for $275 plus shipping. Amazon's shipping is free.

Amazon.com: DENSO 471-1293 A/C Compressor: Automotive

 

From 1998 to 2002 the 320s all used the same Denso compressor.
Here is a brand new Denso for $270. it is not a rebuild. It is on Amazon.
I have gotten one there and an alternator for my E500. If you do not like
Amazon then partsgeek.com has it for $275 plus shipping. Amazon's shipping is free.

Amazon.com: DENSO 471-1293 A/C Compressor: Automotive

Noodles, 471-1293 is correct for 98-2001. 2002 and up they changed to Variable Displacement compressor with different number.

 

The Denso site listed 2002, but I trust your knowledge more.
Is it possible the variable displacement was just for the ML500s?
They show a 471-1474 for the ML500 and a 471-1293 for the ML320.
At least in this case the 471-1293 will work on the 2000 ML320.

I hope I am mot losing my mind. Please take a look here and plug in the info for a 2002 320.
DENSO Aftermarket Online Catalog Search | Vehicle Parts Search

 

Denso catalog is wrong. Since Amazon is using it they are also wrong.

They are both variable displacement compressors. Early version has clutch and round connector. Late version is clutch less and has oval connector.

 

Here are couple of pix.

 

I just got in an early version of this compressor and my c240 has the late version. Can I change the electrical connector and use the early version? I thought that the signal from the front SAM would be different on the clutch and clutchless models. How is the early clutch model variable displacement without a signal from the SAM?

Bill

P.S. Sorry for bumping the old thread.

 

My '98 ML320 has the same issue. Do you more knowledgable members think a leak from the AC Compressor or a faulty compressor are the likely culprits?

My old mechanic found a seal leak in my compressor back in the summer of 2010, which I ignored because he annoyed me, I was moving to upstate NY at the time, and I didn't know much about my car at the time.

I purchased a compressor from a forum member and wanted to try to install the new compressor myself. How hard would it be for me to do this if I had access to a lift (at an hourly rate) and could safely remove/replace the freon?

...Your sage advice is much appreciated

 

With the the use of a lift, replacing the compressor is really not that difficult.

But before you start paying for rack time, it is advisable to make sure that you have all the proper sockets, wrenches and related tools beforehand. Also you will have to buy the (4) O-rings and the drier before starting. You can buy the drier online but the O-rings must be bought from the dealer.

You will need the proper tools to remove the belt and then the proper female torx socket to remove the compressor and related wrenches/sockets to remove the lines to the compressor. All O-rings must be pre-oiled with PAG oil before installation.

 

ac compressor

i am a bit confused now, can one of you guys post a link to the correct AC compressor for ML320 2000 so i can purchase it? and also the mechanic is telling me the dryer has to be replaced as well, it that true?
thanks

 

Here is link to 471-1293.
Yes you will need drier and all kinds of o-rings.

 

Amazon.com: DENSO 471-1293 A/C Compressor: Automotive

 

Compressor

Great I got it, thanks a lot.

 

Thanks 43 and Witek for clearing that up. I would not want somebody to purchase the wrong part based on a post I made and thought was correct.

 

Receiver dryer

I almost forgot, what is a reliable receiver dryer and a good place to buy from?
Dealer is asking $170 for it. way too much.
Thanks to you all

 

Amazon has a Behr/Hella for $30. When you receive the drier do not remove the protective caps. Doing so, the drier will absorb moisture. Remove the caps only when ready to install.

Amazon.com: Behr Hella Service 351200311 Receiver Drier for Mercedes Benz M Class 98-05: Automotive


You can search elsewhere using M/B part number 163 830 00 83.

Please UPDATE YOUR PROFILE.

 

Receiver dryer

Do I have to change the receiver dryer?
Can't I just replace the compressor ? can the receiver dryer be changed later?
Thanks

 

Do I have to change the receiver dryer?
Can't I just replace the compressor ? can the receiver dryer be changed later?
Thanks

The answer to your three questions are, Yes, no and yes, but before you charge the system with refrigerant.

 

It is always recommended to change the receiver/dryer anytime the system is opened. This holds true for all cars from what I recall. Once you undo the lines on the compressor, the system is now opened up and exposed to the air, and the drier is filling up with all the moisture that it gets exposed to during that time. You will also need to vacuum down the system before refilling with R134a.

 

Witek recently got me through a compressor changeout shown in this thread:

http://www.benzworld.org/forums/w163-m-class/1638308-ac-compressor-has-stopped-engaging.html

For a do-over, would have gotten a full MB O-ring set; probably also would have skipped buying the manifold and vacuum rig, and just gone back to the AC shop to evacuate and fill the system. The system only cools to 45 deg F using a thermometer in the center vent (should be 40 deg F), which potentially means that I did not purge the manifold correctly and/or get a good enough vacuum which impacted system efficiency.

Forget the lift and save some money. Did this in my garage with plenty of room.

BTW - $700 for a compressor change including labor sounds suspiciously inexpensive.

 

Thanks

I just wanted to say thanks to all of you guys for helping me find the right compressor, the mechanic replaced the compressor yesterday and my AC is working fine for now, but I am planning to run it every day for a while to make sure it's okay.
Thank again

 

I just wanted to say thanks to all of you guys for helping me find the right compressor, the mechanic replaced the compressor yesterday and my AC is working fine for now, but I am planning to run it every day for a while to make sure it's okay.
Thank again

Im sure a good thank you would be UPDATING your profile with you vehicle model and year. Would be much more better for any future problems you may face