Re: Lark IV Cooling

[Don]

OK, you replaced the impeller, did you use an OEM impeller or aftermarket? You pulled the gearcase down again after you experienced trouble while running in the tank and found no obvious issues, do I have it right? Frank’s advice is spot on, make sure the water level is high enough. You checked thermostat operation, that seemed OK, how about the plastic housing and relief spring/cup at the bottom of the housing, are those pieces OK? Perhaps some debris got caught in the relief spring/cup causing water to bypass the powerhead. The engine won’t cool if the relief cup/spring/housing are not in place/working properly. Finally, have you confirmed that the engine is actually overheating? Like others have said, seeing some steam from the cooling outlet is normal, water spray will be intermittent depending on thermostat operation….