Genset sucking air / Fuel tank access

[Peter Goddu]

I had my generator replaced recently and since the install haven't
been able to get it to run for more than an hour (and most of the
time just a few minutes) before the system starts sucking air, the
secondary fuel filter body empties and the engine dies. The old
generator worked fine, and the shop just used the old connections in
the new install. They've been through it several times looking for
leaks - to no avail. We eliminated the genset itself as the source
of the problem by using a separate fuel source (the supply line stuck
in a 5 gallon bucket of diesel) Anyone else ever had this problem?
Anyone have any suggestions of where to look next?

The genset supply is teed off the line from the Racor. They are now
talking about bypassing that connection and dropping a line directly
into the fuel tank (about 3/4 of the depth of the tank so I can't run
it dry...). Now we're looking for fuel tank access from the top. I
knew there was an access port in the floor of the bedroom) which I
expected would expose the plate for the fuel gauge but when we
unearthed it there was nothing below the access plate. Are there two
access plates? If so, one is going to be under the tile floor in the
galley (groan).

Any/all thoughts appreciated.