Fairly new to boating and boat engines and need some help. I have a 3.7L Mercruiser with Alpha 1 heat exchanger and closed cooling system. Last year boat ran great, but some idling problems. This year engine wouldn't even start and sounded like wasn't getting fuel. I replaced all the fuel lines, cleaned out the mechanical fuel pump, rebuilt the 2 barrel carb, and new spark plugs. Also replaced the torn exhaust bellows with the slip on kind. Turned the engine over in the garage and sounded great, idled beautifully. So we took it out to the lake...within 2 minutes of WOT, smoke begins to billow from the dog box. Engine was seriously overheating and coolant spewing from the overflow and out of the closed system resevoir. Needless to say we had to be towed back to the boat ramp.
Any ideas would be greatly appreciated? Thermostat? Water pump? (it has one I assume). It has never overheated before so I'm not even sure where to start. Thanks.
Any ideas would be greatly appreciated? Thermostat? Water pump? (it has one I assume). It has never overheated before so I'm not even sure where to start. Thanks.