My 92 240 with 140,000 miles started making a noise. Near the vicinity of the alternator/water pump the car makes a noise (hard to explain) that sounds like a meat grinder, or like the whirr that a commercial airliner engine makes at idle. To isolate, I sprayed the belts with dressing, no change. Then, one at a time, I removed the alternator belts then the PS belt to eliminate the water pump, alternator and PS pump as the offender. So what can it be - the timing belt tensioner bearing? Hope the noise is not something serious.
Also, I don't need to replace the timing belt yet, so can I easily replace the tensioner (hoping I don't have to remove the belt, the crank pulley, etc)? What is the verdict, guys? Thanks