I just replaced the 3 alternator bushings a month ago and now noticed that both the front and rear lower bushings have moved forward about a half an inch. In other words, they have come unseated and moved towards the front of the car. I can't figure out why this has occurred, because the long bolt that passes through them is tight as are the others. What normally keeps these lower bushings in place? Could this occur from over tightening the tension adjustment on the alternator belts?

 

The only way for the bushing to move forward,is that they are installed incorrectly. It's easy to do. They should be installed from the center of the bracket,so that the fat ends face each other in the center. This keeps the front bushing from walking forward. Double check the bushing orientation.

 

They were installed correctly, just as you described, that's why I am very puzzled! The front bushing was actually pushed through the hole on the alternator! The lip on the bushing was torn off! That appears to be the only thing that keeps the alternator from sliding forward.

Just had shop perform timing belt install and so I was wondering if it was possible that they somehow tightened the tensioning bolt too much pulling the alternator too far forward and then backed off after realizing what they had done ripping the lip off the front bushing in the process. The pulleys on the alternator are about 1/2" forward of the pulleys on the fan which is skewing the belts and that's what caused me to get under the car and investigate.
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my local volvo speciality shop tells me they only use poly on those alternator and ac compressor bushings nowdays, says the rubber ones fail too easily.

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