Some years ago I acquired a new Manta/Chevette quick rack - original source unknown. Although well lubed up it is very stiff and you can feel the gear teeth engage as the pinion is rotated by hand. In the car the stiffness deadens the feel, not surprisingly and also affects the returnability. The steering can, just, be turned with one finger when the car is jacked up. Backing off the pinion adjustment has negligible effect. Is this case of bad machining/gear matching or is there a way to 'run in' the rack prior to use? ( I have visions of some kind of electric powered oscillating rig in my wilder moments ). Worst case I will have to bin it and get another from someone reputable like Quaife. Any ideas?

I've fitted several racks that have initially felt tight but after a couple of runs have been fine

What car is this on? If it's something like my Jeep, where the entire spring/strut assembly turn the top bearing could be binding with the weight of the car on it.

Edit: ignore just seen what you're building

[Edited on 18/9/15 by joneh]

If backing off the preload makes no difference it sounds like the rack/pinion teeth haven't been cut very accurately.

[Edited on 19/9/15 by MikeRJ]