Memory steer

[MaximRecoil]

I have a rebuilt power steering box in my '69 Charger, and it is tight enough that the car has significant "memory steer", i.e., when turning a corner at an intersection, the car would continue to turn if you didn't center the steering wheel yourself. It does somewhat return to center on its own, but not very well. The old steering box, which I assume was original, never had that problem; it was the typical "steer with your pinky" box, which isn't a wonderful thing, but I prefer it to memory steer.

Is there anything that can be done about this aside from waiting for the box to become worn enough that it turns easier?

[68 RT]

Who rebuilt it? Sounds like the backlash is not adjusted right. If it is that tight your steering will soon be ruined.

[MaximRecoil]

I don't know who rebuilt it; I bought it from RockAuto a couple of years ago I think. Yesterday I loosened the screw on top, the one which is in the center of a 3/4" lock-nut, which helped a little. The FSM said to let the engine idle, disconnect the Pitman arm from the drag link, hold onto the Pitman arm and loosen that screw until you feel backlash, and then tighten the screw about 1/2 turn.

But what is "backlash"?

[ws23rt]

Backlash is a term that describes the free play in a gear mesh.

Gear mesh is the place where two gears become intimate.

Generally when a backlash is specified it is measured at the point of contact between two meshing gears and is the total amount of free space between the gear teeth at the point of mesh.

Also as an aside to this---a "contact patch" is a term that identifies the angular alignment of two shafts that carry gears that mesh. (this is however not applicable to most steering gears as they are fixed by design and can't be changed anyway.

The pitman arm shaft has a gear on it and if any rotating wiggle is felt on that shaft-- that is back lash at that gear to the corresponding worm gear it works with.

Just a bit of --perhaps-- helpful info. from a left fielder.  
BTW Hi Maxim

[jaak]

Does it do it both ways? If you where to jack the car up, and start it, does it turn one way on its own?

If so, the control valve might need adjusting.

Jason

[John_Kunkel]

Control valve adjustment is my thinking too. Can only be checked by raising both front wheels clear of the ground.

[MaximRecoil]

If you where to jack the car up, and start it, does it turn one way on its own?

No, it doesn't. I had the front jacked up with the engine running recently when I adjusted that screw on top according to the way it says to do it in the FSM. I had the drag link disconnected from the Pitman arm so I could feel for backlash while someone loosened the screw, and it never steered on its own the whole time.

The steering has a little more resistance than my old/original steering box, but not so much that it makes it difficult to steer. I've come to the conclusion that the poor steering recovery is because the car isn't straight, rather than because of the additional tightness of the steering box (it's had front damage in the past, most likely from a jump, that was more or less straightened by someone before I got it), and the guy at the Chrysler dealership has to use workarounds to get it more or less aligned (i.e., to get it to go straight down the road without it pulling to one side or the other). After the latest alignment, the steering automatically recovers reasonably well from a left-hand turn, but not at all from a right-hand turn (if I let go of the wheel the car would go in a clockwise circle either indefinitely or for a long time before the steering recovered to center), even though there is no difference in resistance of the steering to either direction. It does go down the road at highway speeds straight though, which is more important to me than the recovery on the steering (which is only really noticeable when making 90-degree left turns).

I should get the chassis properly straightened so I can get a by-the-book front-end alignment. My mechanic friend knows someone who used to work for a Ford dealership, who has a frame straightening machine, and my friend said he'd probably do it for $500 if the engine and fenders were removed. I don't know if that's a good price or not.

[Dino]

Mine kinda does this as well, but not as bad as yours it seems.  I do still have the pinky feel on it though although the box is tight.  Could this maybe be a combo of a tight box and not enough positive caster?

[myk]

I was thinking more positive caster might help also, but in the end that would be just a band aid if the car is bent like he says...

[ws23rt]

Their are several unknowns here.

Let's just address the alignment issue. If the frame is bent and is the reason for a steering problem the guy doing the alignment would/should  find that as a problem. (unable to get to spec.) If a proper alignment can be achieved than the frame is not bent badly or out of factory spec. and therefore unlikely the reason for a steering problem.

[MaximRecoil]

Their are several unknowns here.

Let's just address the alignment issue. If the frame is bent and is the reason for a steering problem the guy doing the alignment would/should  find that as a problem. (unable to get to spec.)

He did find it as a problem, and that's why he had to do workarounds to get the car to drive straight without pulling to the right (such as adding additional camber on the left side to counteract it, or something to that effect). The car surprised him when he test drove it after finishing the alignment. Before he drove it he was very pessimistic, showing me the numbers on a printout and saying that it would always pull to the right because of the nose on the passenger side pointing slightly skyward. After he drove it he said, "Wow, that actually goes down the road pretty good." After I drove it I went back and told him he did a great job considering what he had to work with; the car really does drive straight.

I've known the car wasn't perfectly straight for as long as I've owned it (I bought it very cheaply in 1994, only intending to use it as a parts car at the time). Like I said, it appears to have been jumped, Dukes of Hazzard style (it still wears the remnants of a General Lee paint job, which was applied at some point during the 1980s; the flag on the roof was already mostly faded and weathered away in 1994). You can see that the nose was bent up at perhaps a 20 degree angle at some point; the tops of the front subframe rails are creased, the bottom of the K-member is dented up in, the tops of the inner fenders are all wavy, and some of the factory welds on the inner fenders and shock towers separated.

Long before I got it, someone more or less straightened and rewelded it (it looks straight enough from the outside; panel gaps aren't bad; doors open and close good, etc.), but they obviously eyeballed it, rather than doing it on a frame straightening machine. My mechanic friend thinks the nose needs to come down about an inch and a half on the passenger side, and the alignment guy at the Chrysler dealership also thinks that side needs to come down some. With all the car has been through, I'm surprised it drives straight at all (before I got it on the road in 2011, my mechanic friend thought it would never drive straight the way it was); and it doesn't even have any rattles or squeaks.