Getting the worm onto the shaft.....

I finally found a new worm gear that matches up with the steering sector on my '51 Merc box. Now I need to yank off the old galled gear and press the new gear onto the 46 inch hollow steering shaft. It is a tight interference fit, with a shallow keyway in the shaft, and if anyone has done this press before, would you share how you did it? Thanx.

 

With something like that, I would heat the gear and use a press very gingerly. Very light pressure on a hollow shaft situation. Then to reinstall I would chill the shaft and heat the gear. It has worked for me very well in the past.

 

Heat the gear and press it off. You can install the new gear with a drift and hammer.

 

Thanks, gents. Much obliged.