Would guess that you have same problem that I am working on at the moment in that the rightangle gearing is in the process of breaking up.
I have stripped this down to its component parts and have found metal fragments and damaged bearings.
Expoded diagram is only minor help as it does not appear to show all the parts that I have retreived from inside the housing.
I intend to contact DES Ltd to try and find out the correct parts needed to rectify the problem???
Tom B, June 2009