SMTA Steering Problem

Hey guys I need a little help with this one. My SMTA always binds when turned to the right. Left is no problem at all. So I took the grill and cover plate off this afternoon to try and figure out what was going on. Both gears appeared to be in fine condition and the bearing on the end of the worm gear was ok too. I removed the worm gear and shaft and turned the front wheels by hand easily both left and right to the stops with no trouble at all. I then reinstalled the sector gear a half a turn from where it was (trying to fix the typical wobble) and put the entire assembly back together. Turned to the right and got the same results! Binding hard in the same spot. Turned left and no problem just as before.
So what I'm getting at is this- could it be possible that the steering shaft in the upper bolster that the sector gear mounts to be tweaked just enough to cause a bind? If so how could that even happen? I placed a tape measure over the shaft using a line for reference and it appears that when I turn the front wheels that shaft isnt quite true? The way it's moving now the sector gear gets closer to the worm gear when turned right causing a bind and farther away when turned left causing no issue? Does anyone have any experience with something like this? Thanks for the help DK

Found this problem before and could be your problem. See if the nut that holds the bearing on the end of the worm shaft is contacting inside the bearing retainer cap when turning right. Sometimes a shim is needed between the cap and outer bearing race If the bearing is good.

Thanks for the help! Can I check that by loosening that retainer and trying to turn it? What type of shim would you use to Space that out?

You could, but it would be far easier to fit a shim. You need a shim which is flat washer shaped. I.D. just large enough to fit over the castellated nut and O.D. just small enough to fit inside the threaded section of the sector wheel housing. If the castellated nut is fouling the retaining cap, you should see marks inside the cap where the nut, or possibly just the split pin (I think usually called a cotter pin in the U.S.?) have been contacting the cap. If it is just the split pin the problem is easily fixed by bending it or replacing with a different pin.
SadFarmall

Like sadfarmall posted you should find some marks on the nut, pin or retainer plug if thats the problem. Some that are used without clearance or a bearing that allows front to rear movement for a time will have the nut hex corners rounded and heavy scoring inside the retainer. Retainer plug is to keep the bearing seated in the housing. If you loosen it the shaft will just follow it forward when turning right. Think sadfarmall explained the spacer needed. One that contacts the bearing at the same place the retainer does and will pass through the threads. Or if you have something to grind the inside of the plug that can work. Make sure the shaft bearing is good and look for score marks in the cap before going to a lot of trouble. You may have another problem. Just a guess in post above on my part what the problem is based on finding the same in the past.

Can't remember if there is a thrust ball bearing that the vertical shaft rides on in the lower section of the bolster. Thinking ours went bad one time. Balls were flat or retainer went ker-flooey & let the balls pack up. Probably over-greased it.