I agree with soapy and I guess everyone else.... it would be the worse if you invested money into that pump and it was trash. I was surprised with the prices of the pumps.... it obviously depends on your size but they were 1/3 what I thought they would be.
Not sure if you looked in the housing but there is lots of crap in it.... it would also seem like a lot of trouble to switch it out? But I just replaced mine after someone talked me out of what you want to do.
Oh and my head just fell off.... or my pump head rusted off.