Motors

Here's my problem: Hello e v e r y o n e , Im new to the forum. I have a slight p r o b l e m ! ! ! I have a George Diamond Big Board I p u r c h a s e d approx. 4yrs ago. It c u r r e n t l y has two motors and I have severe dead z o n e s / s p o t s . How can I remedy this p r o b l e m ? ? Or can someone help me with t h i s ? ? ? ! ! ! I truly would a p p r e c i a t e it!!!!! PS: I feel I need better motors or extra motors!!! How can I get them, let alone add them to my board???