Originally Posted by nglitz

My 260E has an idler pulley above the alternator. As an alternative to removing the lower alternator bolt, I removed that idler pulley. It looks to be identical to the puller on the tensioner. There's a plastic cover over the front of the idler pulley and then an internal hex bolt to remove (Allen wrench). After a new belt, the idler pulley can be re-installed by catching the tip of its bolt in the hole and then using the Allen wrench to pull it into position before starting to turn the bolt. Obviously care needs to be taken to avoid stripping the idler's bolt in the process of re-inserting it.

When I first did this in the process of installing a new belt (that probably wasn't really needed) I could watch the tensioner needle swing right up the ramp. A week later, the tensioner died on me and needed replacement. I ran it for a week with a dead tensioner (maybe 200 miles total) and not a squeek. The new belt and the way it wraps around the significant power users (alternator, water pump, A/C compressor) probably help.

OTOH, my daughter's '94 Ford Taurus has the world's simplest serp. belt tensioner. One spring and the tensioner arm has a square hole for a wrench handle. Pull the arm back, swap belts and release the wrench handle. Hard to imagine anything simpler.