OK I have a 5.7 Mercruiser 260hp it is overheating and after about 5-10 minuets it will sputter and die. I checked the thermostat it is ok I am getting water to the exhaust so I assume the water pump in the out drive is good. I do not have water in the oil and the oil level is consistent. I have ran clean fuel from a separate tank and it still does the same thing runs sputters dies it is not a fast kill in the engine that would lead me to think it is not spark. The engine starts to cough choke and backfire then it dies. If it sits for a half hour I can restart it and it will do it again. Note: it is rough to restart. Could this be a bad gasket head or exhaust manifold causing water to mix with the fuel???
Thank you,
Kumi
Also I have removed the circulatory pump it is working fine.
Thank you,
Kumi
Also I have removed the circulatory pump it is working fine.
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