Power Steering Gear adjustment

[Dazz]

How does one adjust the power steering gear? I can't seem to locate the nut or bolt to adjust the steering gear for my 91" XJ.

I want to tighten up the steering a little, it feels to soft.

TIA!

[Eagle]

Too "soft" as in too much power assist? That's standard for the earlier Jeeps, unfortunately. There is no adjustment for that, it's a function of the spool valve in the steering box. It can be changed out for a spool valve from something like a performance package Camaro or Firebird, but now you're talking a lot of work.

If you mean a bit too much slop or free play when going straight ahead, there is an adjustment screw in the top of the steering box. Look closely and you'll see a cover plate with three hold-down screws, and a fourth screw in the center with a slot in it, and a locknut. That's the over-center adjuster. To adjust, back off the lock nut and tighten the screw, then lock down the locknut again.

CAUTION: Over-tightening this screw will ruin the steering box. First, this adjustment MUST be made with the steering gear in the straight ahead position. Second, do not over-tighten. These are recirculating ball steering boxes, not rackety pinion, and you will not/cannot get it to feel as precise as rack & pinion steering.

Also, with a '91 don't overlook the very likely probability that some of your steering looseness may be due to worn/sloppy tie rod ends, ball joints, and/or track bar. Eliminate other potential causes before attacking the steering box.

[forgiven]

On my '89 I must first remove the electric fan to access the adj. bolt/screw.

[Matthew Currie]

Eagle says:

" CAUTION: Over-tightening this screw will ruin the steering box. First, this adjustment MUST be made with the steering gear in the straight ahead position. Second, do not over-tighten. These are recirculating ball steering boxes, not rackety pinion, and you will not/cannot get it to feel as precise as rack & pinion steering."

Read that twice. Most steering boxes are designed to be tighter on center than off, to compensate for wear. Although this varies a little with make, you run the risk, if you tighten it off-center, of having it bind when you straighten it out. A few luckless Mercedes and VW Bus owners have been reported to have crashed when their overtightened steering jammed in place. Recirculating ball boxes will sometimes feel tighter under power than they do standing still, so leave a little room.

[Eagle]

Thanks for the reinforcement, Matthew. That's why I put that caution in there. I've never heard of a Saginaw box being tightened enough to bind completely, but I have known them to bind enough to destroy the box in a very short time. You are correct -- they are designed to be tighter over-center than they are off-center.

I used to mention that you're not even supposed to touch the over-center adjustment until you had removed the box from the vehicle and checked the worm bearing preload adjustment. But everyone ignores that and just cranks down on the over-center screw, so I've stopped telling people how to do it right. :D

[Matthew Currie]

I haven't heard of a Saginaw box binding that badly, though Mercedes has used some Saginaws in the past and I think their design may have been done under license. Some of their boxes are very much tighter on center than off, though. The old VWs used a worm-and-peg gear with no assist, which could bind a little even when it was loose, and could really kill you when it was tight.