David, Do you regularly change the pencil zinc in your heat exchanger? If that zinc has been replaced several times, there is a chance that there are pieces of the old zincs in the heat exchanger. You might consider removing the end cap from that end of the heat exchanger and checking to see if pieces of the zinc are partially blocking that pass of the exchanger. You will need a new end cap gasket. I don't recommend reusing the old gasket.
-- Dennis C. Touche' 35-1 #83 Mandeville, LA On Wed, Jul 23, 2025 at 4:13 PM David Knecht via CnC-List < cnc-list@cnc-list.com> wrote: > I am in the process of installing a new water pump to see if it fixes my > engine overheat problem. I still think the main problem is not enough > water coming out of the exhaust so keying on the water pump. But something > occurred to me today while working on it that I had not thought of before. > Is there a thermostat somewhere in the engine (Universal M4-30)? Can those > malfunction? I presume if it did not open, the engine would overheat? I > don't even know where the thermostat is so have never looked at it but I am > concerned whether that is something I need to check. Dave > > David Knecht > S/V Aries > 1990 C&C 34+ > New London, CT > > [image: pastedGraphic.tiff] > > Your contributions help pay the fees associated with this list and help to > keep it active. Please help by making a small contribution using PayPal > at: https://www.paypal.com/paypalme/stumurray All contributions are > greatly appreciated.
Your contributions help pay the fees associated with this list and help to keep it active. Please help by making a small contribution using PayPal at: https://www.paypal.com/paypalme/stumurray All contributions are greatly appreciated.
