The anchor wash down pump on our hull # 335 SM 2000 leaked from day one. Amel rebuilt it under warranty twice (Laurent in Guadeloupe) but it leaked sea water still. Last year Laurent replaced the pump (again under warranty) with the higher voltage rated pump (I think 32 volts). I believe that the theory here was that the high voltage pump would run slower on the available 24-28 volts and therefore be less likely to generate as much pressure and be less likely to leak. Nevertheless, the new pump leaks at the same parting seal despite never having been turned on. I believe now that the surging pressures in the sea chest (called "housing" by Amel) and the associated plumbing may put too much pressure on this style of pump seals. I have wondered about putting an accumulator tank in line here to dampen pressure surges. I would be interested in the experience of others.
I have purchased a Graco bronze vane pump with pressure switch. I am anticipating replacing the Amel anchor wash down pump with this one and in the process doing away with the sea water feed. I want to plumb fresh water to this pump and hence to the anchor washdown. I am also anticipating putting a valve and a hose bib in the forward port locker to accomodate a deck wash down system using this newly plumbed fresh water system. Has anybody else out there done this? Any potential drawbacks to this? The only things I have worried about are: 1. The size of the fresh water plumbing coming from the fresh water tank, is it too small? Will the vane pump cavitate or not hold prime? 2. The pressure rating on the plastic tubing that runs from the anchor washdown pump to the bow of the boat. I don't want to blow a hole in this tubing. Any thoughts on either of these two items.