Hi Rod. We do not have any information on that Rover model number in the manuals section, so unless Bruce can upload something, we are stuck. The model number is also not recognised by the Murray web site.
We need a lot more information to understand what you are saying. First, what is the Model, Type and Code of the Briggs engine? Second, why is the starter motor activated when you are running the engine? Is it an all-in-one starter and alternator?
If you clarify these matters, and post some pictures, we can try to make a start, but unless we get access to the wiring diagram from the manual, it is going to be difficult.