Steering pin shim adjustment

[TeriAnn]

I'm trying to adjust the shims on the top steering pin of the swivel housing (right side)

The steering was rebuilt with new bearings & bushings 6 years ago, and recently I've been getting slow speed shimmy whenever the front right wheel hits a slight uneven surface.

What I'm finding with the spring gauge is if I pull the arm out ( away from the engine) it takes about 18 lbs to overcome inertia then as the arm swings out the spring pressure rapidly drops.

When I pull to the left (towards the engine) the arm doesn't budge until the spring pressure is in the neighborhood of 30-40 lbs and the pressure is well above 15 lbs as it turns.

The manual insinuates that the spring pressure would be the same in both directions.

Any idea what is going on and how to fix it? I'm running real short on time.

TeriAnn

[o2batsea]

Did you put in new bottom bearing? Is the Railco bush new? Did you reuse the old top pin? I ask only bc the pin could be out of round slightly. That would make it bind in one spot.

[lumpydog]

Another thought - the resistance measurement is supposed to be done without the swivel seal on, which will add its own drag - albeit unevenly due to it reaching it's limits near the extremes. I've spoken to at least one well know restoration guru who leaves the seals on and "just knows" the relative increase in drag/change in behavior and can set it that way... When I tested mine with the swivel seals on (after setting the drag to about 14 lbs with the swivel seals off), I think the resistance was around 21lbs but it was uneven/less smooth similar to what you describe.

[parrie]

Another thought - the resistance measurement is supposed to be done without the swivel seal on, which will add its own drag - albeit unevenly due to it reaching it's limits near the extremes. I've spoken to at least one well know restoration guru who leaves the seals on and "just knows" the relative increase in drag/change in behavior and can set it that way... When I tested mine with the swivel seals on (after setting the drag to about 14 lbs with the swivel seals off), I think the resistance was around 21lbs but it was uneven/less smooth similar to what you describe.

2nd on having the swivel seals removed when setting. I recently did swivel balls on both my dormie and my Ninety...both w/o the seals installed. I checked again upon installing the swivel seals and I was surprised at how much extra drag the swivel seals create...an extra 10lbs at least.

[TeriAnn]

Thanks for the comments.

I ran out of time to do this before leaving for North Carolina so I decided to treat it like a field repair. I took out a medium shim, buttoned it back up and pulled. Way too tight. I replaced that shim and took out the thinnest one. The pull seemed ballpark once the initial pull resistance was overcome. I reassembled everything and took the truck to the places that had caused a low speed shimmy. No shimmy, so I called it good enough for the trip.

My front disc brake conversion has 2 bolts on each side torqued to 150 foot pounds. There is no way I'm strong enough to deal with those to remove the front axles, so good enough will have to do for new.

[parrie]

Sounds good enough! Safe travels and good luck in North Carolina!