One of the spring jobs that I’d not written up but what has made a huge difference is some work on our freshwater pump. We have a Marco UP3/e gear based pump. It’s excellent and varies it’s speed to match the flow demand. I’d hoped it would self prime, but in our installation it doesn’t and needs a knurled bleed screw opening for a moment when we change tanks.
After six or more years use the need to prime it had increased and it might struggle to empty the tanks. That was partly due to some deposits on the valves on the breather lines, but stripping and polishing those in May 2025 didn’t entirely resolve the issue.
This spring I bought a service kit for the pump – essentially two new helical gears, an O ring and new face plate. It was pretty trivial to install – though the gotcha is not to tighten the faceplate too hard, as over compressing the seal presses on the end face of the gears and prevents them from turning.
The pump had always been rather noisy with a high pitched whine. It was it’s Achille’s heel for us: I love the robust, durable pump, and variable flow but the noise was an irritant. It didn’t help that the pump was mounted to a shelf inside a locker under the saloon sofa that acted as a sounding board amplifying the noise.
This spring I pointed my AI agent of choice, Perplexity, at the problem and it came back with a pile of sensible suggestions about installing the pump on a noise isolating raft. £10, including postage, got me four rubber mounting bushes, each with an M4 thread protruding on both sides. I used them to fix an 8mm offcut of HDPE sheet floating above another that with some spacers under it could be fixed to the original shelf, whilst the pump was mounted to the floating raft, plumbed in with flexible hose.
It was a huge success. The noise levels dropped dramatically. Still audible but there was no longer a need to raise your voice or wait till it stopped.