How do you replace the tensioner assembly on a 1996 Plymouth voyager mini van?

The pulley can easily be removed from the tensioner by loosening the bolt in the center. (the same one you use to loosen the tension to put the belt on.

put a socket wrench on the bolt (mine is 15mm) and loosen. once the bolt is removed the pulley will come right off.

tighten the bolt with the new pulley in place until the bolt pulls against the spring loaded tensioner. turning the bolt tighter will also loosen the tension to replace the belt. I found that threading the belt in place over the tensioner pulley first and then releasing the tension while I slide the belt onto the alternator pulley worked better because the wrench was in the way if I try to put the belt on the tension pulley last.

good luck getting it loose enough to get the belt on. two people would make the job a lot easier.