I have an RC18B Factory Team Kit. I got a Futaba S3103 servo for it. The servo does not work very well. It locks up if I try to steer sitting still. It works OK (still locks up sometimes) when moving. Does anyone have a suggestion on what servo I should try instead? I tryed a HiTec servo, but it doesn't fit in the servo mount. This is my first car, so I am new to the hobby. Any help would be very appreciated.