I seem to recall a similar issue when raising my mast. I was using the older style mast step link. I purchased the newer stiffer model and have really liked it. No side-to-side wavering and no jumping up like you've described. Here's the Murrays pic:
![[Linked Image]](http://i88.photobucket.com/albums/k192/skipper0802/16maststeplink.jpg)
Hope this helps your mast hinge behavior.
Fair winds,
Eric