Chart plotter/fish finder issues need some help

[Poncho]

Hi guys my name is John I would like to take this opportunity to introduce myself to the boat forum as this isy first boat. I just picked up a 2002 Parker 1801. With a raymarine a60/a65 chart plotter and fish finder. The guy I bought it from was a great guy and was up front and told me the issues it had. The unit works great other than two issues. First issue. When I shut boat off to drift And turn it back on i get a power surge and it kills power to the fish finder chart plotter and it shuts off. Second issue is for the life of me I cannot figure out how to change the time and date on the unit. And there is nothing in manual about changing date and time it say Previous owner (an Engineer) couldn't figure it out either. If you guys could give me any insight on how to fix these problems it would be greatly appreciated.