MERCEDES W203 C180K: V-BELT CAUSE FLIPPING NOISE WHEN TURNING ON AIR CONDITIONING

hi all,

belt flipping noise problem has happened ever since I was living in Nottingham. the flipping belt noise will appear whenever AC is switched ON.

Symptom and troubleshooting:

1) V-belt slip from its place when AC is ON causing very noisy sound from the engine compartment. 

solution:

1)below parts need to be replaced

alternator pulley

tensioner pulley

idler pulley

Parts:

1) Idler Pulley (cost about RM70)

2) Tensioner Pulley (RM80)

3) Alternator Pulley (RM150)

Tools:

To replace alternator pulley, special tools are required as shown in the below picture.

the black color tool called  V-Belt Pulley Center Bolt Removal Alternator 33T Socket Tool which costs less than RM10 from the online retailer.

Two option on how to replace alternator tensioner:

1) ask the repair shop to remove pulley for you, but you need to disassemble the alternator and bring it's to the repair shop or

2) buy the special tools shown in the picture above and replace them by ourselves.

I choose option 2 because the cost for the shop to do replacement and the cost of buying special tools is almost the same. So, instead of asking the shop to replace it for me, I decided to do it myself and gain some experience and knowledge.

Work procedures for V-belt removal:

1) Secure the vehicle on a level surface.

2) Block both sides of the wheel.

3) Remove the air intake to MAF

4) Remove the charger compressor airflow pipe

5) Remove v-belt
6) Installation in reverse order

Work Procedure for Idler and Tensioner Pulley

6) Once V-blet is removed, proceed to the next step
2) Remove nut the holding both idler and tensioner pulley. No (1) is idler pulley and no (2) is tensioner pulley which hiding just behind cooling pipe

3) Replace with new pulley

Work procedure for Alternator Tensioner Removal
1) Prepare tools as below

2) prepare access to the pulley

3) Remove the pulley by following the force direction (arrow) as in the picture. (might need extra force to release it. So, use the high-quality tool, otherwise, you might be breaking your tool)

4) replace with new pulley

Belting Arrangement for W203 Engine M271:

please refer to below diagram for V-belt installation because you might get confused with belt layout

Thank you for reading. Hope this helps.