Thank you for your help on Friday. I really appreciate it. Your suggestion to go to AutoZone and get a radiator pressure test kit was spot on and resolved everything. After pressurizing the system to 13 pounds I discovered some small hoses leading to and from the heat exchanger chamber were leaking ever so slightly. It only took a few turns on the hose clamps and the system held pressure up to 14 pounds for six hours.
The Neuse River water is pretty cold now so after a 30 minute warm-up the engine leveled off and held steady atat 150°. Seems to be holding coolant just fine now.
I dont know if Beta Marine engines cost more than other marine diesels, but with customer service like you provide, I certainly think they are worth more.
