The pulley on my AC compressor has a bit of play in it. I originally thought I would have to replace the entire compressor to fix this ... but after poking around a bit on the internet I found that you can replace just the bearing:


... at a cost of $20-30 vs $400-500 for replacing the entire compressor and dealing with the refrigerant evacuation and recharge.

Also, there is a Mercedes technical service bulletin stating that you can replace the clutch bearing without removing the compressor from the vehicle.

However, I am having a hard time finding the specific bearing to purchase.

Here is a pic of the label off my compressor:



Showing it as a Denso model 7SEU10c, Denso part #447180-9712.

Based on this guide -- https://www.carid.com/images/denso/a...ts-catalog.pdf -- The current Denso model for our M271 engines seems to be #471-1580.

However I am having a very hard time finding info on what bearing to purchase. There are at least a few different sized bearings sold for Denso AC compressors. I am, however, able to find the complete pulley/clutch assembly for sale, part #0002341412 ... but it's ~$200.

Has anyone replaced just the clutch pulley bearing on their Denso compressor?

Can you provide me with any help in locating the correct bearing?

Thanks. John

** UPDATE ** I was able to find results when searching for clutch pulleys ... found some online that specify the bearing as 35x52x22mm. I also noticed from the pics that the bearing seems to be held into the pulley channel by little divots stamped into the ring surrounding the bearing. I wonder if it will be possible to remove the bearing from the pulley without destroying the pulley (which appears to be made of plastic.). Pulleys seem to be readily available on eBay from a German manufacturer (TTK) for $50-70. I couldn't find much info on TTK so don't know if that is a reliable brand ... I did send them an email to ask where they source their bearings from ... they said C&U and Taide, both Chinese bearing companies.

 

Try this website, just put in your car specs and it will show you a diagram as well as pricing.
https://www.mbpartsworld.com/

 

Unfortunately none of the MB parts ordering sites carry compressor parts ... only the entire compressor. On some I can punch in the part number for the clutch/pulley assembly, but they don't provide much info.

 

hi

we're you able to replace the bearing? my compressor works but it makes noise as I Rev up the engine.

thanks

 

Sorry, I haven't gotten around to it yet ... a couple weeks back I got under the car and tried to loosen the center shaft but couldn't hold the pulley firmly enough to keep it from moving ... so went to Home Depot and bought a shear tie-down strip and a few M6 bolts, I am going to try making my own MBZ AC clutch holder tool to fit in those three holes. Still haven't gotten around to that yet, but when I do I will post my results.

 

 

This AC compressor doesn't have a clutch.

 

Sorry, I haven't found the time to work on it yet. There is really no issue though -- just putting together that pully holder tool so I can break the shaft loose.

Personally I would rather replace the entire compressor as the car is 13 years old now and I'd like to get all of the front accessories replaced with new ... but as I haven't been using the car much I've been putting this off ...

-- John

 

I just replaced the AC Compressor clutch on my 2001 C240. Very simple job, except the bearing was so destroyed, the inner race stayed on the compressor shaft when I took off the pulley, and I had to use a two-jaw bearing puller to get it off. Other than that, nothing really to take apart. I was able to get the bolt off while the serpentine belt was in tension, then there is a snap ring that needs to come off after the clutch cover is removed. Then the pulley pulls off. I got a rebuilt pulley and clutch assembly from Jenson Auto in Michigan. Very good service, and the part was only $60. Came three days after I ordered it. Everything works fine. Probably save a couple grand over the stealership because they would replace the entire compressor.

 

I managed to replace the pulley on my 2006 E280 M272. But I lost the flat washer on the shoulder of compressor shaft, Can any one please help about the inner and outer diameter and its THICKNESS. Thanks!

 

so you can do this without removing the comp from car? I just ordered a clutch set from ebay

 

Good luck with that.

 

 

 

thanks, will be tackling this weedend

 

here's a vid of my noise I pulled the belt and the and it just about fell apart

 

 

IMHO that sounds more like the guts of the AC compressor (piston/valve clatter?) rather than bearing noise which is usually a whirring sound. Is your AC fully charged?

Fyi these cars are over 10 years old now ... if you plan to keep the car long term I suggest eventually replacing all accessories on the car, including kompressor.

 

Like I said before, good luck with that. If the pulley fails on you CLUTCHLESS compressor, there's something wrong with the compressor itself. You need to replace the whole thing. Replacing the pulley is not going to fix the underlying problem.

 

It's not looking good. The shaft will not break away from hub. The shaft bolt is not 7mm socket as described in video, it has 2 flat sides and 2 rounded sides. I can only get my adjustable to grab at it, and in turn it wants to round off. It maybe going to a mechanic.

The compressor itself cools fine the noise goes away when comp runs

 

That's what I thought too but the noise goes away or at least get alot quieter when comp engages. I think it's the rubber bushings and bearing failure

 

To find out which pulley(s) is(are) making loud noise, you may use a plastic pipe about 1m, one end place near to the pulley and listen to the noise. Be VERY CAREFUL not to touch the pulleys or the belt when engine is running.

 

Btw, I found out that the little washer has the specification of : 17(outer dia) x10 (inner dia) x3mm (thick). Just to share this information in case any one miss place it. Without this washer (spacer), the pulley cover will break once a/c is on.

 

 

The failure is internal to the compressor, likely the variable swash plate mechanism. The compressor is always turning eveb when it's "off" so it wears out much faster than a traditional clutched compressor. The clutchless setup went through several generations during the w203 production run so finding the correct part for your specific compressor is extra fun. I converted mine to a traditional clutched type compressor. It's far more reliable.
Bypass belt:
Duralast 910K6" or 6PK2310