Quiet the macerator pump

We had what we considered excessive noise coming from our macerator pump. It was not enough to alert zombies, but there was a bit of a drumming / reverberation noise in addition to the “standard” pump noise. We felt a couple of minor tweaks to the way the pump was mounted may provide some improvement, so here is what we tried.

Isolation Grommet

The pump is suspended from the utility bay by a bracket that is bolted to the side of the bay. We thought that adding a isolation grommet between the bracket and the side wall of the bay would improve the situation.

You can find a variety of rubber grommet’s at the hardware / big box stores. We selected on that a bolt would just fit through. We then enlarged the mounting hole and installed the grommet and reattached the bracket. We used washers on each side of the grommet so it was gently compressed and also used a nylon locknut to secure it (you don’t want to torque down on the nut, you just want to compress the grommet)

Isolation Mount

On that same bracket on the pump mounting end, we added a rubber washer between the pump body and the bracket. This partially decoupled pump vibration from being transmitted up the bracket to the bay. I later used a rubber strip that was placed between the pump and the hose bracket to completely isolate that area (sorry, don’t have a picture)

Result

Overall the above really did help to lower the noise that was being produced. In the original mounting any vibration was coupled right to the bay and it acted a bit like a steel drum. Now the only noise is the sound of the pump itself, which if your tanks are full, and you have to go, can be a pleasant sound!