After Winterizing and Spring time comes

[bkwarford]

I purchased a 1985 Chris Craft - Scorpion 186 boat this year and I plan to winterize the boat myself later in the year. I've always done automotive maintenance and so the process shouldn't be demanding for me but I have a general question. This boat has an I\O Mercruiser V-8 5.0L 200HP motor. I've ordered a repair manual for the motor this week but was looking for a answer to the following question to end my curiousity of the internal cooling system before the manual arrives. <br />As I understand from other web searches most of the I\O motors have an internal closed cooling system inaddition to the external water cooling system thru the lower unit. And that the internal system needs to be drained before winter time. But my question is when spring time comes and I'm ready to return to the lake do I need to refill this internal cooling system some how? Or does the motor pull water from the external system to fill the internal system? I've briefly looked over the motor and didn't see a visible 'radiator-like' cap for easy access to the cooling system.

 

[MFG197]

Re: After Winterizing and Spring time comes

should be in Mercruiser I/O section, but<br /><br />most I/Os used in fresh water are open systems. Seawater is drawn in either by an intake on the boat or through the outdrive. It then goes into the thermostat housing and is circulated through the block by a automotive style ciruclating pump. the water then gets moved into the exhaust manifolds where it is then ejected overboard with the exhaust. The sea water cools the engine, manifolds, and exhaust. Some boats do have a heat exchanger (like a radiator on a car which intead of air uses water) which uses sea water pushed through a heat exhcanger that cools the coolant in the block. the sea water goes overboard and the coolant stays in the closed system.<br /><br />If your boat has an open system that has been drained all you have to do is start the engine in the water. never start the engine without water attached.