Merc 25hp fuel / ignition problems?

Question
Hello Ron,
I have a Merc 25hp from 98 and I have rebulit the carb w/Merc kit. The old membrane was torn so I thought it was fixed. But now the engine starts and runs but when I open the throttle it dies.It re-starts after but the same thing again-dies. Someone told me that if the impeller is bad the engine overheats and it cuts out? Is this possible? I have good compression and spark, but feel that it could be an electrical problem? Any ideas??
Thanks,
John

Answer
Hi John

Thank you for selecting the undersigned to reply to your question.

I'm not a mechanic, but yes, if the engine is not being properly and adequately water cooled, the pistons can and will seize. The impeller is like a pump, and draws fresh water into the journals of the engine to keep it cool. I can't imagine how this could affect the carburation. Best you consult a qualified Mercury marine mechanic.

Safe Boating
Ron Blanchet