Keith, I agree with everything you say from the technical side, but
have a few quibbles from the practical side...
At 03:20 PM 6/28/2009, Keith Hughes wrote:
>>So, is it fair to say that a noisy FP may be caused by the pump delivering
>>too much volume?
>No it isn't.  Cavitation *reduces* the liquid volume being pumped.

If you understand Dave's statement as implying "too much output [for
the current inlet conditions to deliver without exceeding the maximum
suction head]" then it makes sense.

>being high enough to create gasoline vapor bubbles (not "vacuum"
>bubbles - ain't no such critter in a fluid system),

Vacuum is a relative thing in our earthbound existence -- I submit
that if there's a small enough amount of vapor that the bubbles can
collapse violently with noise and destructive potential, that calling
them vacuum bubbles informally is quite legitimate.

>Wrong approach - you need to fix the actual problem which is a suction
>side flow restriction

Agree in principle.  However when you have a threshold cavitation
problem that's not fixed by removing the inlet filter, I think
slowing the pump could potentially put off more serious repairs for a
long time.

>you are now.  Slow it enough so that the regulator can't maintain 45psi

C'mon, Keith, clearly nothing I've suggested contemplates cutting the
pump output in half, quite the reverse.  :-)

Cheers,
David

  --
David Beierl - Providence RI USA -- http://pws.prserv.net/synergy/Vanagon/
'89 Po' White Star "Scamp"