ASR33 carriange stopper issue

[Martin Meiner]

Hello guys. 
I recently acquired for a mere 25 EUR a nice ASR33. Aside of needing a thorough cleaning and greasing, it seems to be pretty much working fine! 
But I wouldn't write here if I wouldn't need your help: 
The ASR33's carriage has a spring that gets tighter as you type. And upon CR, the spring will bring the carriage back to its original left position. There is a mechanism, similar as a piston and a cylinder, which acts as a "bumper" or stopper. My problem is that this stopper, while not showing any signs of usage, seems too tight. If the carriage is all the way to the right, the spring will be strong enough to overcome the "too tight stopper". But if only a few words were typed followed by CR, the force is not strong enough to bring the carriage to its left home-position. Of course I could take down some of the piston's diameter to overcome the problem. But this doesn't seem right. 
Anyone out there also had a problem with this stopper being too tight to bring the carriage to its home position and how to overcome it? 
Thanks for any advise on the issue. Martin