Eheim 2217 Impleller Problem - Please Help Me

Hi Friends !

I have a problem / doubt regarding the Impeller Assembly of the Eheim 2217 and just wanted to request for guidance. Kindly help me here, Friends...

Today, When I removed the Impeller to clean it for the first time, I noticed that I could remove the following parts -

1. The Plastic Fan like thing - The Impeller
2. The Cylindrical Magnet which attaches to / below the Impeller
3. The Thin Ceramic Rod, which I guess is the Shaft
4. A Single Rubber Bushing which connects to the Shaft End (the end which is near the Fan like thing, not the end which goes inside the Pump's End.

Now if you look at the following pic (for reference)



I'm not able to pullout the Rubber Bushing on the Pump's end - The one which I've Marked with a Red Colored Square in the pic. No matter how hard I try, I cant pull it out.

Just wanted to know if this is the way its supposed to be or should I be able to pull it out easily. If yes, then is this a problem ? I'm asking this because - Is it supposed to be moving freely inside, so that the Impeller can rotate freely ? Is it supposed to come out easily ? How do I pull out this Bushing which seems to be stuck inside ?

Kindly guide me friends, I'm really worried that this might be a serious problem and that my Filter might stop working soon because of this.

Awaiting your replies and help...
Regards
Kush