Need a bearing for Lamona hja8513 - Ovens

GOOGLE KNOWS check link below

https://www.google.com/search?q=How+to+replace+Lamona+hja+4610+fan+oven+element&oq=How+to+replace+Lamona+hja+4610+fan+oven+element&aqs=chrome..69i57&sourceid=chrome&ie=UTF-8

Contact Lanona to request the diagram.

Have a look at https://www.howdens.com/appliance-collection/ovens/lamona-double-fan-oven/

Easiest thing to do is to Get your Model Number, log onto www.searspartsdirect.com and order the new knobs... Or go to your local appliance repair center or Appliance parts store and order them and you will be able to get fix it for the future.
Download LAMONA HJA 3300 HJA3300 User Guide English

may be an internal fuse / wire burnt off oven control as nothing works

Try this link it might help
http://www.docstoc.com/docs/71826497/Lamona-Double-Fan-Oven---HJA4560-Lamona-Built-Under-Double-Fan-Oven