NH 918H Flail Bearing Issue

[jgbanshee]

I have a 918H flail mower that I am trying to change the flange bearing on the one side. I had to use a puller to pull the old bearing off the shaft. I thought the flange bearings were a slide on fit. The shaft dia. measures 40mm on the money, so did the old bearing. I bought a new 40mm 4-bolt flange bearing and it will not go on the shaft more than a half inch. How can I get it on?