R2800 cutting out

[Daddio]

Engine: P&W R2800-CB3 probably from a DC-6
Application: wind generator (ground use only)
Symptom: stalls out during operation with almost no warning. For a few seconds prior to cutout, the fuel pressure wobbles a bit, then starts dropping fast. She will recover with boost pressure. Intermittent boost application will prevent the stalls, but I want to fix what's wrong.
So, what's wrong?
I recently replaced a very leaky engine-driven fuel pump. I thought a slight shaft seal leak in the boost pump was causing stalls due to sucking air bubbles into the line, so I also replaced the boost pump. I have not found a fuel leak in the 20' of line running up to the engine, but some of it's covered up; I'll be dismantling things later.



Question: What else can cause her to just drop out like that, or am I positively looking for a fuel line leak sucking air?

Fuel pressure during a normal run is about 22½ psi. With boost, it climbs to almost 25 psi.

Thanks!
D²

[engguy]

Did you get this figured out yet?

[FLYBOYJ]

Did you check for water in your fuel system?

[operator18]

Check the vapor return line or there could be a problem with the auto rich control.