[quote author=Tris link=topic=2824.msg18291#msg18291 date=1590489699
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It makes a terrible noise inside the boat (wall trembling) as well as outside which wakes up our neighbours every day.
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Shower evacuation pumps are not the quietest in operation, but are your pump mounting bolts/screws loose thereby allowing the pump to rattle around ? You could try mounting it on some thick rubber to absorb any vibration.
Another possibility might be that the pump suction filter could be blocked. If you can’t remember when you last cleaned the filter then it’s most likely overdue. On my boat the filter has a wire mesh within, this can be pulled out and the attached crud then washed away into a bucket for suitable disposal.
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Thanks for the tips.
We have already put rubber between the bolts and screws. And clean the filter every week.
so looking further