I am attempting for the umpteenth time to install the power steering pulley on my 95 5.0 f150. Yes I have the proper tool but when I tighten the nut and hold on to the jackshaft the pump shaft turns and rotates the jack shaft back out of the pump shaft. What the crap! Any help would be appreciated.

 

If you have the proper tool, you need to run the center bolt down tight, then turn the nut to press the pulley onto the shaft.
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I've tightened the installation bolt on to the end of the jack screw but I can't get the bolt tight in the pump without the shaft turning. Is there a way to restrict or clamp the pumpshaft without damaging the new pump

 

There is no special way to tighten the center bolt, I always use a 3/8" butterfly impact, it'll spin only after it bottoms out and tightens. What may help is if the tool you're using has a bearing on the surface contact point with the pulley, if you have just a bolt and nut with a washer, add another washer with a coating of grease between them.
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