Questioni have an 04 sonata 2.4. had the timing belt change for maintenance at about 60,000 miles. 2 days later the p/s serp belt outer rib was cut off and about 2 weeks later, the alt belt did the same thing. put another and the same thing happened. the mechanic looked at it and thought the tensioner was bad. 2 tensioners later, the belt doesn't cut but squeals. it sounds like the tensioner bearing squealing more than a belt squeal. if i loosen the belt till the noise stops, the belt starts to slip. have tried different brands and qualities of belt. one note. while running, i tried to tighten the tensioner locking nut some more. it wouldn't but the noise stopped while i had the torque on it.
the work was done by a hyundai tech but on the side. any ideas where he went wrong?
AnswerI don't know that the technician did anything wrong, but it's possible the tensioner pulley was too tight on reassembly or that the tensioner bracket was somehow bent or misaligned during servicing. I'm presuming that the issue is with the P/S-A/C belt.
First, try to get an idea of the origin of the noise.
With the engine running, spray a little WD-40 or similar lubricant onto the belt. If the noise changes, you've just determined that it's caused by the belt's interaction with at least one of the pulleys. Assuming that the tensioner pulley and belt are good since they've been replaced, you likely have at least one misaligned pulley. Take a look to see whether any are obviously out of position or cocked at an abnormal angle. If so, you'll then need to determine why this is the case. If the tensioner pulley is still at issue, the pulley may not have been properly aligned when the locking nut was installed-- this is my personal best guess. To resolve this, you may need to pry the tension adjusting bolt to hold the pulley aligned while tightening the locking bolt. If the power steering pulley is at issue, the most likely causes are a worn power steering pump bearing or misaligned mounting bracket. This bracket is the same one to which the tensioner pulley mounts. If the crank pulley is at issue, the most likely cause is that the pulley is coming apart.
If the issue is not changed with the WD-40, with the engine running, carefully take a long screwdriver and probe the tensioner pulley's lock nut or non-rotating center section opposite the nut. Then place your ear on the handle end. If you can hear the noise prominently through the screwdriver, the noise is probably in the pulley bearing. I don't find this very likely, since you've already had two pulleys installed. If necessary, you can probe around to other components to attempt to locate the noise further. For example, if you were checking the water pump and pulley, you'd probe the pump body itself.
