Power steering self centering adjustment

[Tool.Man]

The Chrysler manual on page 19–20 describes under “test and adjustments“ a process to adjust the self-centering feature. My steering wheel wants to roll counterclockwise, the left. With the car running I tap on the head of back pressure valve body attaching screws.

I have tapped until I’m blue in the face and nothing changes. Note that I start with the steering wheel centered as I begin to tap and invariably it rolls over to the left.

I need some help before I take a hammer to the whole thing.

 

[Professor Fate]

Silly question, but you DID loosen the two bolts, right?
Loosen them just enough so you can tap the valve forward or backward, and the valve doesn't leak.
I forget which way (forward or backward) makes the steering go which way, but it's not too hard to figure out. Once you've got it so it will stay centered, tighten the two bolts back down. It doesn't need to move very far at all.

Red arrows show the two bolts, green arrows show the directions the valve can move.

 

[dadsbee]

^^^^ Fwd.. backwards, not side to side.

 

[toolmanmike]

Subscribed. Mine rolls to the right just a bit. We were talking about that a few weeks ago. One way or the other. Loosen the bolts just a bit, tap it, and retest. @lkopaska was telling me how he adjusted them when setting new cars up at the dealership.

 

[A56]

 

[toolmanmike]

Thanks for the link.

 

[Tool.Man]

Silly question, but you DID loosen the two bolts, right?
Loosen them just enough so you can tap the valve forward or backward, and the valve doesn't leak.
I forget which way (forward or backward) makes the steering go which way, but it's not too hard to figure out. Once you've got it so it will stay centered, tighten the two bolts back down. It doesn't need to move very far at all.
View attachment 1716451843
Red arrows show the two bolts, green arrows show the directions the valve can move.

Not silly. No. I don’t have the manual where I am now, but I didn’t pick up on it if it’s there.

I’m certain as I can be without the manual, but it said to do the tap test while the car was running but that won’t work if the screws are loose. Wednesday, I’ll do as you describe.

Assuming I get the self-centering fixed, I then need to adjust the preload to remove the slack in the steering wheel. With the car running, I was judging the slack by watching the input shaft while twisting the coupling with my hand, careful to recognize wiggle between the coupling and the shaft of which there was very little. I was doing the centering wrong. Am I doing the preload correctly? I couldn’t get the play out.

I put in a $200 O’Reilly’s rebuilt. Have you guys had good luck with those?

 

[Tool.Man]

Silly question, but you DID loosen the two bolts, right?
Loosen them just enough so you can tap the valve forward or backward, and the valve doesn't leak.
I forget which way (forward or backward) makes the steering go which way, but it's not too hard to figure out. Once you've got it so it will stay centered, tighten the two bolts back down. It doesn't need to move very far at all.
View attachment 1716451843
Red arrows show the two bolts, green arrows show the directions the valve can move.

I’m not seeing your image. Do I have that turned off somehow?

 

[dadsbee]

Glitch in the matrix right now! Joey is working on it ...

 

[Professor Fate]

Not silly. No. I don’t have the manual where I am now, but I didn’t pick up on it if it’s there.

I’m certain as I can be without the manual, but it said to do the tap test while the car was running but that won’t work if the screws are loose. Wednesday, I’ll do as you describe.

Assuming I get the self-centering fixed, I then need to adjust the preload to remove the slack in the steering wheel. With the car running, I was judging the slack by watching the input shaft while twisting the coupling with my hand, careful to recognize wiggle between the coupling and the shaft of which there was very little. I was doing the centering wrong. Am I doing the preload correctly? I couldn’t get the play out.

I put in a $200 O’Reilly’s rebuilt. Have you guys had good luck with those?

I reloaded the picture, hopefully it stays put now that the system updates are done...
Self-centering MUST be done when the engine is running. You only loosen the bolts enough to be able to tap the valve back and forth, not so much that it starts to leak; as I said.
I have no experience regarding the quality of an O'Reilly rebuilt steering box, maybe someone else out there does.

 

[Bewy]

Not sure if this applies to Mopars. I know the steering wheel attaches to a splined shaft. Same with my Pontiac. But with my P, there is no master spline so the steering wheel might be 'centered' but where it attaches to the s/box it can be off of centre.

 

[Tool.Man]

I did get the steering to properly self center. I’ve attached a photo of the instructions from the Chrysler manual to prove I’m not a total idiot. Nowhere does it say, “loosen screws“.

 

[Tool.Man]

Attached is a photo from the Chrysler book on sector shaft adjustment.

I don’t see why it’s necessary to disconnect the center link. It seems to me that if while the car is running, you move the steering wheel back-and-forth very slowly and watch the left front wheel, if there’s only a hint of delay between moving the steering wheel and the wheel itself moving, then there’s no slack but that doesn’t assure the proper preload.

Does anyone have a proven process for making this adjustment?

 

[Tool.Man]

So the sector adjustment is complete, but the steering wheel still rotates counterclockwise just a little. I have loosened the two screws to the point of leaking and used a hammer and a rod to beat on the head of the screws with no difference. What now?

 

[harrisonm]

Silly question, but you DID loosen the two bolts, right?
Loosen them just enough so you can tap the valve forward or backward, and the valve doesn't leak.
I forget which way (forward or backward) makes the steering go which way, but it's not too hard to figure out. Once you've got it so it will stay centered, tighten the two bolts back down. It doesn't need to move very far at all.
View attachment 1716452386
Red arrows show the two bolts, green arrows show the directions the valve can move.

Thanks for the picture. We had this discussion a while back. If you are leaning over the fender, forwards and backwards (towards front of car and towards back of car) will seem to be side to side.

 

[67Dart273]

It's always possible that something is wrong with the valve, or dirt caught in there someplace

You have to realize these are a servo type device, a feedback loop, sorta like cruise control. They are easier to understand if you have ever seen the kind with a cylinder on the drag link, and the valve on the end of the tie rod. Corvettes used these until quite late. Don't know why, or when they quit. The valve has some play, so when you move the toggle it operates the valve, and the valve boosts the power. When you quit moving the wheel, the boost keeps going, so to speak, until it moves far enough to move the toggle "loose" (centered) and close the valve.

Frankly I'm surprised they last as long as they do.

 

[1WildRT]

So the sector adjustment is complete, but the steering wheel still rotates counterclockwise just a little. I have loosened the two screws to the point of leaking and used a hammer and a rod to beat on the head of the screws with no difference. What now?

You don't beat on the head of the screws.... You lightly tap the valve body, it slides maybe 1/8" total but if it moves to either end of it's travel the wheeling wheel will be spinning till it hits the end of it's travel...

Look at the machined groove in the steering box picture below, the valve can only move within the groove....

Don't worry about the red arrow, pay attention to the groove, the valve slides in that groove... tap either end of the valve with the engine running & you'll see the effect... The tires should be off the ground... When you get it so it doesn't turn to either direction with the wheels in the air you are close... Shut the engine off & watch the steering wheel as you start the engine.... The wheel shouldn't move at all, if it briefly kicks to either side your adjustment needs further tweaking... If it doesn't move tighten the bolts & top off the fluid....

In the service manual they mention tapping on the bolts... What they are referring to are the bolt and cap with the red arrows in the photo below...

 

[Bewy]

Sounds like you have an internal leak from valve or seal.

 

[Tool.Man]

You don't beat on the head of the screws.... You lightly tap the valve body, it slides maybe 1/8" total but if it moves to either end of it's travel the wheeling wheel will be spinning till it hits the end of it's travel...

Look at the machined groove in the steering box picture below, the valve can only move within the groove....

View attachment 1716463405
Don't worry about the red arrow, pay attention to the groove, the valve slides in that groove... tap either end of the valve with the engine running & you'll see the effect... The tires should be off the ground... When you get it so it doesn't turn to either direction with the wheels in the air you are close... Shut the engine off & watch the steering wheel as you start the engine.... The wheel shouldn't move at all, if it briefly kicks to either side your adjustment needs further tweaking... If it doesn't move tighten the bolts & top off the fluid....

In the service manual they mention tapping on the bolts... What they are referring to are the bolt and cap with the red arrows in the photo below...

View attachment 1716463407

Good stuff. I understood the referenced screws to be the two that secure the valve to the box. “Beat” is an exaggeration but I did resolve the worst of the problem tapping vigorously on them. I’ll give it another try. Thanks.

 

[toolmanmike]

I remember @lkopaska saying he would bring a ratchet, extension, socket and a small hammer on a test drive to make those adjustments while setting up new cars at the dealer.