There is an older Johnson trolling motor on our 17ft Lowe boat that I know NOTHING about. It is a 12V motor and has a 2-blade prop. I need to know what pound thrust this motor is.

I just got a used minn-kota 24# thrust trolling motor that is in good shape. It is a 12V as well with a 4-blade prop. My question is would I be better with the Johnson or replacing it with the Minn-Kota?