based on reviews I have been quite lucky that the vac motors and pump have lasted through as many jobs as they have - I always run defoamer through it every job and acid rinse in my prespray and not the solution tank as well as running for 10-15 minutes with lid off to dry vacs! so far its holding out and it is being sold next week > my Mytee 1005dx is 10 minutes away in a warehouse and its driving me nuts!
I'm not here to argue, just to say that I have 400 hours on my ETM. So far, knock-on-wood I haven't had a problem running an acid rinse through my pump. I do run a couple gallons of fresh water through it at the end of the day.
I don't even use acid rinse in my solution tank > I put it in my prespray! the only thing that runs through my solution tank is defoamer and I am looking into getting a defoamer kit so I don't even have to use that! straight water is best in solution tank > nothing more