Mercruiser 165 over heating problem

[Blue_Heron]

Thankyou, I will try it. Someone else referred me here and I was just hoping someone would know. Thanks again.

Mercruisers have several cooling system options for each engine type. Don's right, someone who's familiar with the engines that were installed in the Bayliners of that era is more likely to have the answer you're looking for. There may be someone here who can answer your question, but most of us are outboard guys.
Dave