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Matt, Mechanical Engineer
Category: Mercedes
Satisfied Customers: 22731
Experience:  BEng hons Mech engineering, in auto industry 22 years
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Merc.slk230 1997. Kompressor makes tapping sound even with

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Merc.slk230 1997. Kompressor makes tapping sound even with brand new replacement.Not continuously. Can I have this corrected?

can you tell me whats been replaced ?
Customer: replied 5 years ago.

The Kompessor unit has been replaced with a new Kompessor unity.No improvement.

Customer: replied 5 years ago.

Kompessor noise is not uncommon in older Mercs. The reason for this phenomenon does not seem to be widely known,even by experts.

Customer: replied 5 years ago.
16/3/2013 @17.18. I have not received an answer to the question I submitted re.Mercedes Kompressor noise. John Maleady.
Hello John

in the front of the compressor there's a soft coupling to connect the pulley to the compressor rotor and there's enough compliance in this coupling to allow a 'rattle'

this rattle can be set off by a number of things

I'd first try removing the auxiliary drive belt and turning every pulley and ancillary ( power steering pump , alternator etc) by hand. All should turn easily (with the exception of the AC pump) with no grittyness or wobbly pulleys- If you do find a sticky pump / alternator then it should be replaced or repaired
If the engine is stone cold you can briefly run it with no belts to see if the noise changes or has gone away, this will help show if an ancillary is the issue

Matt and other Mercedes Specialists are ready to help you
Customer: replied 5 years ago.
Hi Matt Thank u for your suggestions on the Kompressor problem They all sound quite feasible. Only problem is that when I checked sound through long screwdriver I found that the rattle was almost certainly coming from inside the Kompressor unit itself. It seemed unlikely that the sound was coming from outside of the unit. Maybe I am wrong on that. I spoke to a Merc. Mechanic about the problem and found him quite vague on the cause.My reason for contacting your organisation was that you might have encountered the problem in the past and being neutral might be in a position to offer a solution.Thanks again. John Maleady
Hello John

yes the sound can originate from inside the kompressor but its likley that the point of origin of the vibration is from another part - hence my suggestion