It was Sigmar. page 8 in this manual for the isolation idea.
http://www.sigmarine.com/support/Manual.pdf
If your box mounted to the bulkhead without touching the
pump or hoses I bet you'd have nearly silent operation.

Matt

"Gordon Wedman" wrote in message
news:NQdlb.30567$At.15615@edtnps84...
Right now the wooden box is just sitting on the hull with 1 inch of medium
density foam separating the two. Could be that making the box was the
wrong
way to go because it has just made the vibrating mass heavier. I'll have
to
do some experimenting.

"Matt/Meribeth Pedersen" wrote in message
ink.net...
Gordon,
I think either Dickinson or Sigmar recommends mounting the
aux fuel pump on an isolator. Their version is an old radiator hose
screwed to a bulkhead, and the pump screwed to the hose (but
not into the bulkhead). Have you tried that or is the noise
something different?