...okay, so I took the plunge and bought 2 MP40s and the battery backup...set them up last night and all I can say is....WOW !!!....these things are waaayyyy too much fun. the amount of detritus that came flying off the rocks and immediately lifted from the bottom was AWSEOME !!! The fish seemed to love the flow...they were like kids at recess (although, they had no choice...hahaha)...they also are quiet...not sure why people are saying they are loud?...my refrigerator makes more noise....anyway, I love these things and hopefully they will stand the test of time.
The reason people say they are loud(and will argue till the cows come home and say it isn't so, but whatever)and wear wrong I have found by messing and fixing others recently is two fold: First, that they aren't aligned right. Those things will vibrate horribly/loudly if they are 2mm off (at least the ones I have had and others that I have worked with) and sometimes it really takes patience. Next, as I have found, if you have the pin spacers off, then they wear and heat. Then, there is the rubber on the back of the dry side that you have to "make sure" is sitting flat(when doing it's job, it "will" take up any imperfections that possibly could be in the glass. There is a very apparent "sweet spot" that, once you get one there, you know how it sounds.
Then, if you have the two combined, it doesn't take a ton to imagine what happens. The thing is, and nothing against anyone (but it is what it is), but not everyone has the same precision. With that in mind, your going to have failures, loudness, etc.
People may not like it, but the truth is the truth. I personally have fixed 5 pair of pumps recently simply because the people saw and heard mine, spread the word and I have become "alignment dude". I don't mind because they are fellow refers, but that is what I, and a few others I know have run into with them. People will argue till they are blue in the face until you fix it in two minutes, then they look goofy.
Maybe you have to have an ear or something, because when it's close, it can still be off a bit, resulting in it vibrating way off over a day to a few weeks. Not sure, but I haven't run into one I couldn't fix as long as it hadn't been damaged from the vibration. One thing that I did notice on a 10 I worked on that was only a few days old, is that it doesn't take long at all to damage them if they are off. That's just another little mental note I remember.
And lol, any company with an ounce of desire to succeed will do "customer service"on you, which is not to say "it's your fault", but if they charge you, lol, they are saying it's your fault overall. That's just a great customer service rep. No one is ever at fault when something goes wrong, but a person will hang themself if you just listen to their story. I'm not saying there aren't failures, but not that many in the overall scope of things. They just aren't for everyone because they do require a bit of precision that not everyone has.
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