Another note: Regarding the motor dying at idle turned out to be air in the fuel line. There was an old electric lift pump abandoned in place in series with the fuel line. With all air purged from the line, before removing the motor, it was not a problem. Once the line was opened however it became an issue. I removed the old lift pump and installed a manual prime bulb in location after Racor filters. After about 50 squeezes
with the motor running all air has been purged and I have not had a problem since.
I probably need to find a new electric lift pump but have not found the time to research yet.
A year later the motor is still running fine. It starts first try even when very cold out. Down south here the boat stays in the water.
The valve backlash on this motor is adjusted like the valves on an old VW engine. The manner in which the motor is mounted in the boat leaves no access to periodically check valve backlash. I will fix this this summer. Valve backlash was the root cause of the motor stopping...they became so loose that the push rods literally fell out of the rocker arms. There were other issues as well as the motor had been in the salt for a number of years and cooling passages were plugging up with sea critters and unidentified crud. I cleaned all passages including those in the cylinder head.
I was told that the cylinder heads are no longer available. Fortunately mine was okay. They are quite heavy / crude so should be rugged.