Are you sure your fuel filters are not plugged?? My 941b went from full load pushing to stalling out in about 90 seconds from a clogged filter.
The fuel pressure gauge reads the pressure after the filter and is there to give you an indication of when you need to change the filter. On IHC machines it even told you on the gauge.
Later Bob
Hi
The one I ran for years--had a small strainer--before the pump and filter
Look for it--
when it would be hard to start--that was the quick fix