Hello Eric,
Is your gas tank original? If so it is quite likely that the
gas tank is deteriorating on the inside and crap is plugging
the line to the pump. Pull the line off the tank and see if
you get good flow from the tank - catch the fuel and be very
careful to not cause a fire. I had a similar problem and had
to replace the gas tank.

I doubt very much that adding the vacuum line would cause
any problem.
Good luck,
Tom
Burlington Ontario
84 Westy - beautiful condition - FOR SALE -
www.shopmiduss.com/westy
85 Westy 1.9L
85 Parts van
86 Van

Eric Wrote:

Now for the problem - the new pump is making the same
noise!  I am
thinking that I should drop the tank and flush it out.

I can still drive it and the buzzing isn't as bad (although
audible). It
still hesitates and bogs down when I accelerate hard. The
engine is
slightly underpowered (to what it was last week) and I need
to get it
fixed soon as it's now my daily errand-driver (I bike to
work).

Any ideas / similar experiences?  I was wondering if this
was the result
of bad gas or grime in the tank.   I haven't checked the
output of the
new pump (and I really should I guess).

This may be related or not but I had to splice in about 4
inches of
rubber vacuum line on the thin solid plastic (yellow?)
vacuum line that
runs from the pressure regulator (diaphragm) on the front
drivers-side
corner of the engine compartment to the passenger side of
the intake
manifold vacuum port. It's on there pretty tight and the new
hose is
solid - no chance of it collapsing under vacuum pressure.

Any hints / directions would be invaluable.

Thanks,

Eric
'80 Westie "Rusty"