This is just a working theory and kind of far fetched but......

IF the evap system was blocked, would the fuel pump then create a
vacuum and cause the pump to cavitate? If so......

IF the evap system had been leaking at an expansion tank(s) or
elsewhere but the evap system gets sealed up (repaired) would this
revealed a blockage in the evap system in the form of pump cavitation
noise?

The last time I had my fuel tank out, I noted that one of the black
nylon evap lines had been pinched between tank and frame. Image
looking up at fill neck hole: http://tinyurl.com/pfpe82d

that hose runs to the charcoal canister. IIRC, the black nylon line to
the evap rollover valve got messed up so I ended up shortening that
line a little. I think this pulled it up putting it in a position
between tank and vehicle frame.

Neil.

On 11/30/14, Geneva Saint-Amour <genevasaintamour@hotmail.com> wrote:

> Hey listers. We are in sunny Baja MX and thought we would toss this out for
> discussion.
> Some time ago we replaced the fuel tank. At that time we moved the filter to
> post-pump location. All was great and quiet.  About a month ago we replaced
> the seals on the expansion tanks. Now the fuel pump is making quite a bit of
> noise.
> Thoughts or suggestions are welcome!
>
> Geneva and/or Mike Saint-Amour
> www.slowcarfasthouse.com
>

--
Neil n

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