I'm helping dad out with his 53 XK-120 roadster steering box. It was leaking badly and I volunteered to replace the seals and pretty it up a bit. In order to get to the seal on the shaft going to the drop arm, I need to remove the drop arm. Should be simple enough according to the workshop manual but this particular box (date coded 03-54, so not original I'm guessing), has a big pin through the arm. The castle nut and split pin were also present. Is this stock or did someone drill a hole through the drop arm and splined spindle and push in this pin? I tried some moderate tapping to see if I could get it to move but it is stuck. I'm not sure if it is tapered so I'm not even sure which way to push. Any thoughts on this? Thanks in advance, Craig.

Pin is sticking out on this side.

Pin is below the surface on this side.

 

I have to say, having looked at the Jaguar drawings, that this pin doesn't look correct as it is not shown on the parts drawings. It is of such a diameter as to surely affect the strength of the rocker shaft at that point. What secures the other, (idler) arm ?

 

Thanks for the reply, Fraser. (I'm used to seeing your name on the MK1/Mk2 forum where I spend most of my time). The pin is not shown on the parts diagrams or in the original workshop manual. The idler arm is stock.
I'm now fairly certain that some one added the pin, but I'm not sure what problem it solved. The car did have a very bad shimmy at speed decades ago but that turned out to be alignment related, according to dad. The car was hit sometime in the late 50's and the frame is slightly bent, no doubt adding to the alignment issues. The complete steering column and box were replace with the subject second hand box sometime in the 70's thinking that this would solve the problem but it did not.
The good news is that the original column and box turned up at dad's place today. I'm going to focus on that box as it was likely fine to begin with.