Snap on Piece not "Clicking"

[JohnnyBlondin]

I am hoping to find some help with a build I am doing with my son. I am stuck at a part where it says it's "Snap on" and video's I have watched all say that I should here a "click", I am not getting it to click or snap on? Anyone else experience this, any tips? 

[Juggular]

I built 3 dozen Tamiya kits. None of them snaps on.  

What they mean is that you should push the shaft into the keyed shape in the gears.  The ends of the shaft are sort of oblong in shape. You should rotate the "GB2" gear until they go in fully.  That's what they mean by "snap on."  It has no clip or anything to make the snapping sound. It doesn't even take any force to do it either.  

The Japanese translation says, "Push it all the way in."  That's it. No clicking, no snapping. I'd say 'snap on' is one of those funny translations.