The F6 is more than enough. It's for big blocks
The F5 pump is more than enough
A full system will require a 5" diameter heat exchangers or larger
For plumbing a full system it may be easier to run two in-house thermostats.
Water flow on raw water side..... from seacock and sea strainer...
Gapping alone may get you home , but it isn't accurate it in the +/-40% range
Dwell needs to be correct to get coil saturation so that when the points open, the magnetic field is as strong as possible when it collapses and energizes the secondary windings providing the coil output
The meter...
I would pull the pump, the plastic reservoirs are known to crack after 15 years
That will allow you to inspect and clean the reservoir
The only way water enters thru the cap is if the pump was submerged
Most likely one of the cylinders has a seal leak. The hydraulic seals last 15-20 years
the safety lanyard is usually just a break in the ignition wire. so if its not working, nothing back to the engine will work.
follow the purple wire from the key switch, it then goes thru the safety lanyard, then to the motor.
I would have pulled the carb apart by now and been out a few bucks for gaskets.
regarding fuel pressure, its either there or not. most intermittent issues are not fuel supply related as the fuel bowl in the carb has enough fuel in it to run for a few minutes.
the fact the motor runs at...
The filter at the carb will pass small rocks. It's about a 100 micron filter. The spin on one is 11 micron. Look at the water separating filter....looking for water
