[Doni]

A couple of weeks ago, the AC compressor clutch on my wife's '04 C240 shattered and took the belt along with it. I was planning to get around to R&R'ing the compressor this weekend but a package arrived yesterday with the wrong compressor (7SEU16 vs. 7SEU17C.) The problem is both my wife and I needed our cars this weekend so I had to come up with something....or rent a car for one of us.

What I decided to do, since the shattered clutch left enough clearance for it, was to install a shorter serpentine belt eliminating the AC compressor temporarily. But searches on this and other MB forums gave me no hint as to the belt needed to do so.

Thanks to the patience of AutoZone staff and a couple hours of trial and error/back and forth, I found that the perfect belt to do this was their "Duralast 910K6" or "6PK2310" (same belt-different number.) Just pull back the tensioner, run the belt from the PS pump directly to the crank pulley instead of where the AC pulley would normally go and the job's done.

A 100mph road test for 10 miles proved that it worked like a charm!

 

[rudeney]

Good job! Another trick for this is to measure the length of belt you need by cutting the old belt (if it isn't already broken) and running it through the system. Mark the length and then have the auto parts guy lookup belts by length and width to match.

 

[jelecroy]

Thank you for posting this advice. The length specified in the manual for the short test belt is 2315 mm, or 91.14 inches, so the 91 inch Duralast belt works fine. I used this to get my car back home when the compressor seized a couple hundred miles from home. Works great.
Jerry

 

[DaODB]

Hello, I was wondering if this could be a long-term fix? And how hard is it to bypass the AC Compressor? I have had a whining noise (I think it is getting louder) coming from left side of engine. Some say Power Steering, others say AC Compressor. Pretty sure it is AC Compressor. Increases on RPMs.

Even though I live in Florida, I am just a teenager... I can't afford the large cost of a new AC compressor. Could you give tips on how to do this change of belt? Thanks.

 

[vr2whf]

I suspect I need the AC compressor to be replaced soon. I feel the brake pedal shaking slightly whenever the AC turns on.

Any R&R for the AC compressor? Do we need to refill the refrigerant when doing the AC compressor replacement?

 

[rudeney]

Replacing the belt is easy. I can actually do it without any tools, although the "prescribed method" is to use a wrench to release pressure on the tension pulley (#7 on the diagram linked below). You can definitely use the A/C bypass belt permanently. Note that in the diagram, you will have the bottom setup (i.e. with A/C). The bypass belt will go straight from the crank pulley (#1) to the power steering pump (#3). It will just clear the top of the A/C compressor pulley (#2).

As for replacing the compressor, If it's actually the compressor pump that is the problem, you will have to recharge the system because removing the compressor does open it. And anytime you open the system, you also have to replace the dryer/receiver and the expansion valve. If it's just the pulley bearing or clutch (you can't rotate the pulley by hand with the engine off), that can be replaced by itself without opening the refrigerant system.

If you get some vibration from the A/C compressor, first check to make sure that the pulley and clutch are installed tightly, and that the compressor itself is securely bolted. A bad compressor usually won't cause any noticeable vibration.

 

[vr2whf]

Hi Rudeney,

Can't see the diagram. I don't find the link at your post. BTW, how to access the AC compressor and the associated clutch/pulley? Do we need to access from the bottom or even need the left wheel wall removed?

Thanks!

Replacing the belt is easy. I can actually do it without any tools, although the "prescribed method" is to use a wrench to release pressure on the tension pulley (#7 on the diagram linked below). You can definitely use the A/C bypass belt permanently. Note that in the diagram, you will have the bottom setup (i.e. with A/C). The bypass belt will go straight from the crank pulley (#1) to the power steering pump (#3). It will just clear the top of the A/C compressor pulley (#2).

As for replacing the compressor, If it's actually the compressor pump that is the problem, you will have to recharge the system because removing the compressor does open it. And anytime you open the system, you also have to replace the dryer/receiver and the expansion valve. If it's just the pulley bearing or clutch (you can't rotate the pulley by hand with the engine off), that can be replaced by itself without opening the refrigerant system.

If you get some vibration from the A/C compressor, first check to make sure that the pulley and clutch are installed tightly, and that the compressor itself is securely bolted. A bad compressor usually won't cause any noticeable vibration.

 

[jaymh16]

Hi everyone,

Just had the exact same thing happen to me as I was 1000 miles into my drive from LA to Dallas. The A/C completely seized and the pulley is no longer turning. The idler pulley broke into pieces...Luckily It happened in a city with an O'reilys nearby. I've ordered the idler pulley and have the belt specified above. Does anyone know if the belt will pass between the AC pulley and the tensioner? Even if it just works temporarily I was planning on bypassing it so I can get home. Can't afford a full compressor replacement in this small town. Stranded at a hotel until saturday when the part arrives.

Thanks for any help!!

 

[rudeney]

That belt should work. I can't attest that the part the OP listed is correct, but the proper length belt will bypass the compressor and allow you to drive.

 

[MingTsu]

Thank you Doni, the bypass belt worked great for me. Going to price the compressor around and may end up changing it myself if they charge an arm and a leg!

Thank you again, it was a great idea!

 

[fernmc]

Great idea! I would like run the engine of my 2004 (W209) CLK320 without the A/C compressor. This is to confirm whether the whining noise is from the A/C compressor. A shorter serpetine belt would do it. I read the post above suggesting "Duralast 910K6" or "6PK2310" for a 04 C340. Is that engine the same of the 04 CLK320?

 

[rudeney]

The C240 and C320 use basically the same M112 engine (the 240 is de-stroked for less HP and displacement), so yes, that would be the same belt.

 

[vwfreak]

Please help! Can anyone tell me if this would be the same belt used to bypass the AC pulley on a R-Class 350 6 cylinder? I'm about 900 miles from home on vacation and the AC pulley just broke off.

 

[rudeney]

I don't believe it's the same belt, but here's what you can do. Go to an auto parts store and get them to lookup the belt you need. Then, used the old belt to measure the circuit without driving the compressor. Serpentine belt part numbers are based on length and number of ribs. Once you know the length you need w/o the compressor, they should be able to get you one that will work.

In case you need the routing diagram:

http://benzbits.com/M272/BeltRouting.pdf

 

[vwfreak]

Thankfully I broke down at a gas station in Alachua, Florida with a crappy hotel across the street. Had to stay there last night and discovered there was a Advance auto parts store only a mile away. In the morning I took off the shredded belt and looked up the dimensions of the original belt and compared the specs of the the belt everyone is talking about and it was about 4 inches shorter. I used part of the old belt that was still complete and cut it and used it to get a idea what size I would need not routing through the AC pulley and it looked about right. I called Advanced and they had 1 in stock Thank GOD!!! I said don't sell it I'll be there in a few so I packed up the family and everything and drove the mile with no power steering and put the belt on in the parking lot. It worked great and was on the road by 10 am. I drove 600 miles to Tennessee today through in extreme 100° heat and a very miserable family but at least we're driving.

 

[rudeney]

What was the belt part number you bought? I am sure someone searching this thread in the future would want to know!

 

[vwfreak]

6PK2310 The same belt # that was used in the first post of this thread. The belt was $21 from Advance Auto Parts. I would recommend anyone with a fear of something going wrong with the AC compressor run out and buy one of those belts and keep in the car along with the correct size socket for the tensioner mine was a 17 mm on the R-class 350.

 

[Seksas08]

im having great luck last week the rear window regulator today the ac compressor clutch. do you think the belt would work for 2005 clk500? probably not right? since its a v8

 

[rudeney]

The M112 V6 (xx240, xx320) and M113 V8 (xx430, xx500) engines what are called "modular". They use the same block, just 6 cylinders for the M112 and 8 for the M113. They also use different crankshafts for the difference in displacement. Most other parts, including the serpentine belt, are the same. SO, you can use the aforementioned bypass belt on your CLK500.

 

[Seksas08]

The M112 V6 (xx240, xx320) and M113 V8 (xx430, xx500) engines what are called "modular". They use the same block, just 6 cylinders for the M112 and 8 for the M113. They also use different crankshafts for the difference in displacement. Most other parts, including the serpentine belt, are the same. SO, you can use the aforementioned bypass belt on your CLK500.

A/C AC Compressor Clutch Mercedes-Benz 2003-2010 (7SEU17C) CA-165 | eBay and i checked mine it looks exactly the same, def aftermarket. i think MB want you to replace the whole thing like the damn regulator. lol i was gna send this in a msg but it says you exceeded your limit in the inbox