Replace your fuel filter; that's what worked for me with same symptoms.
RichSan Diego

      From: Doug Toomey <drt@UOREGON.EDU>
 To: vanagon@GERRY.VANAGON.COM
 Sent: Tuesday, June 21, 2016 6:30 PM
 Subject: Buzzing fuel pump

Hi all,

87 Westy, on a trip. Fuel pump is buzzing. Replaced original Bosch that was also buzzing loudly 5 months ago. New one is Bosch too. No problems on the new one until today. Any ideas? Thanks!