Originally Posted by cruising7388
Is there a significant incidence of macerator failure that doesn't involve owner negligence or abuse?
Hard to tell for sure, and I do think the failure rate we hear about lately is less than it used to be. It is possible, though, that people have heard enough about the failures to kind of expect them to happen so we don't hear about them as much. Over the same period, it appears the failure rate hasn't changed noticeably on marine applications, at least from the little bit of looking I have done on the boat forums about it.
Some people have repeated failures and some essentially none, so user style certainly appears to be part of it.
Another part of it could be that a lot of the failures were on the Chevy Roadtreks, and IMO, the installation could be part of the problem. Chevy Roadtrek sales are way down so less units to fail. The pump on the Chevies, and maybe some other Roadtreks, is mounted upside down, which can cause a couple of issues. It puts the inlet of the pump at a higher point in the feed pipe so the area doesn't get pumped out completely, in the upside down position the "weep" hole in the chamber between the pump and motor is pointed up instead of down, so a minor liquid lead will fill the chamber and go into the motor, and also the Roadtrek added rod to the end of the motor so you can turn it to free up a stuck pump removes a solid plug in the motor so water can now get in and destroy the motor. There is a thread with pix on the forum showing it all and how to fix at least some of the issues.
The good thing about having a dual dumping system is that it is invisible when not needed, requires very little attention and maintenance, and the removing of worry about a pump failure is gone completely.