that is a 3.7L 165 hp engine. It has the 4" heat exchanger (the good one), and external alternator conversion(some one already did you a favor). The 2bbl Mercarb, and an aluminum manifold with a cast iron riser. first things first, check the gasket between the riser and manifold, it should have one edge of the gasket that goes straight between the mounting bosses, the other side will scallop between the bosses. If it doesn't have the straight edge on one side(indicates what gasket you have) I suggest replacing it with a factory mercruiser gasket. Second thing, do a search for pertronix ignitions, get the conversion kit, you'll thank me and every one else that recommended it later. Set the timing at 4 degrees BTDC. If you can find a large throttle body 2bbl Rochester marine carb off of an 898. 888, 200,230 mercuiser, you will be happy with the swap, if you can find a 4bbl carb/intake/oil cooler setup, you'll be ecstatic. Looks like the charging system has been taken care of. Look around the balancer for signs of anti freeze, there is a weep hle that lets antifreeze out of the cam shaft drive seal starts to leaking, . If it passes snuff, you will have good use out of the motor.
A picture really is worth a thousand words.
