Jim and Gerry,
        I had this very same situation in my '81. I took out the tank and
cleaned it (it wasn't dirty inside) with alcohol and blew it out with
compressed air through every tube and pipe I could see. I then replaced and
tested all the parts Jim mentioned all for nought. The pump still whined so
I finally got a different gas tank and it whined no more. An undamaged tank
is hard to come by since the boneyards move the vans around with fork lifts
and bend the bottom of the tank. A tank with a slight bend will sometimes
work I tried two and the second tank (less bent) worked. One word of warning
is that the fuel level sender float may sit up on one of these bends inside
the tank and tell you that you have gas when in fact you don't. I know about
that! I think that any year tank will work but you might have to change the
filler pipe I had to do this with the later than '84 tank I tried. Good luck!

Rick Koller
'90 syncro Westie
'81 air Westie
***************************************
Richard Koller
Email: rkoller@helix.nih.gov
Phone: 301-496-8414
***************************************