My neighbor has a motor similar to mine and I am thinking about swapping the
foot with him to cut this problerm in half but that is a lot to ask.

Greg,
That would be a quick easy thing to try. But you are right, it's a lot to ask.
In a perfect world your dealer would have one to try. I would not be happy
bringing my boat in for repair, paying good money, only to find out it wasn't
fixed.
The possibility of a blown head gasket /cracked head is there, but I would
personally eliminate the lower unit/ water pump first.2PSI doesn't sound like
much water pressure at 4000 rpms. What is the spec on it?

BR

2PSI doesn't sound like
much water pressure at 4000 rpms. What is the spec on it?


The best I can tell it is 16 lbs.
I had it out tonight and I start out at about 4.5 psi until the thermostat
opens and then I am back to 2 or so. I really think the water supply tube or
the manifold must be plugged. with limited flow the pump pressure will max out
at a pretty low RPM (water starts blowing by the impeller), then more RPM won't
do much for the pressure.
I am really thinking if I get back in there myself I will make a snake from a
screen door spring and snake out that pipe.