Thanks for all the feedback and info folks - sure enough it was the oil pressure switch (actually the electrical connection tab to connect to it had broken rather than the internal switch itself) - should have been obvious if I had been looking in the right place. Anyway, new switch, 5 minute installation, and we are back in business!
Nathan Post S/V Wisper 1981 C&C 34 Lynn, MA _______________________________________________ Thanks everyone for supporting this list with your contributions. Each and every one is greatly appreciated. If you want to support the list - use PayPal to send contribution -- https://www.paypal.me/stumurray