For those people who have jumped with interest on the possibility of looking at a valve in the fuel pump(s) - I would ask how they explain the almost exactly simultaneous occurance of this previously unrecorded (?) problem in two separate pumps (albeit working in similar conditions) and the even more remarkable fact that the power (i.e. fuel passing) ended up almost exactly the same through both affected pumps.
If this was a single incident the pump theory might well be worth looking at. However, the real problem is the simultaneous, and almost completely similar, effects on both engines/fuel systems.
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