The instructions on how to change the Mercedes serpentine belt (also known as Drive Belt, Poly V Belt) apply to all Mercedes-Benz cars with six and eight-cylinder gasoline engines such as M112, M13, M272, M273, etc.
Changing Mercedes-Benz serpentine is an easy task and requires about thirty minutes.
Symptoms that you need to change your Mercedes-Benz serpentine belt include squealing noise (most noticeable at startup). The serpentine belt may show signs of cracks damaged ribs.
Other possible symptoms include powering steering noise, poor air conditioner, and battery warning light.
Do not ignore your serpentine belt if it shows signs of damage. If the belt comes off when the engine is running, it can cause unnecessary damage to engine components.
Place a 17mm socket and ratchet on the tensioner and move the tensioner UP. Turn the wrench counter-clockwise.Some models have a Hex bolt in the pulley center that can be used to release the drive belt. Do NOT use the secure TORX bolt to release the tensioner. Use the 17mm nut below the pulley.
Insert a pin (such as a 6mm Allen wrench) into the locking hole. The tensioner needs to be all the way up to be able to insert the locking pin.Make sure that the pin is strong enough and is inserted properly.If the pin is not inserted in the proper hole or is not inserted fully, it can snap off and cause damage or body injuries.
Remove the old belt by sliding the belt away from all the pulleys.
Install the new belt. Route it over the powering steering pump, A/C compressor, crankshaft, alternator, idler pulley. It is important to take a picture of the old belt before removing it and using it as a refepulley. It is important to take a picture of the old belt before removing it and using it as a reference.Otherwise, you will be wondering how to route the belt. The serpentine belt routing is printed on top of the upper radiator support or under the hood on some cars.
Typical routing of Mercedes Benz serpentine belt. Whenever possible, take a picture of the old belt routing before removal. The drive belt routing diagram may be printed underneath the hood or top of the radiator support.
Instructions on how to change the Mercedes-Benz drive belt apply to the following models. These instructions may apply to other models not included in this list.