T9.9 fuel pump question

[elorimer]

I have two T9.9 EXRY engines, from 2000. Today, while motoring for about 3 hours, the port engine died three times at about half throttle, at widely separated intervals. Each time I pumped the primer bulb (which seemed soft) and the engine started up promptly and ran fine for another good long while.

The temperature was about 85 degrees. This engine has the original fuel pump, while the starboard engine has the new pump with water cooling.

Does this sound like the fuel pump is going bad, or a heat problem the new style pump was intended to address, or might it be a carb float problem?

[rodbolt17]

I would say that for whatever reason fuel is not reaching the float chamber.
all the primer does is bypass the pump to prime the float chamber.
is it "making" oil?

[elorimer]

No, it doesn't seem to be making oil. Normal level and it doesn't smell gassy.

The primer doesn't actually bypass the pump, does it? It just forces gas through the pump?