I've been working on a bunch of little parts and pieces as I try to get all the engine ancillaries and plumbing sorted. One job finally came together today.
I machined up the belt tensioner idler a few weeks back and figured I'd finish it off. I machined a nut that matched the water pump and PS pulleys in style. I wanted to set it up so there was no need to use a spanner on the nut and it would be smooth looking. Hopefully the pics will make sense as to how it works.
Here's the idler pulley with the retaining nut in place.
Here's the back of the nut and the shaft so you can see the key setup. The nut is keyed to the shaft so it won't rotate
This should show how the nut keys to the shaft. The bearing for the idler is clamped in between.
Here's the mounting bracket. It's retained with the water pump mounting bolts. There is a slot machined in it and in the end there's an adjuster screw that pushes the idler shaft along the slot. The shaft is machined so it keys into the slot and cannot rotate.
Here it is with the belt in place. It's dead easy to tension the belt up. Just loosen off the retaining bolt at the back. Wind up the adjusting screw in the end of the bracket to tension the belt and then tighten the retaining bolt at the back. Job's done.
Cheers