Pentair LA MS05 failure

Mar 5, 2019
Tallahassee, FL
Hi Guys,
I appreciate all the help you’ve graciously given.
I pulled my Pentair LA MS05 hoping to replace a bad bearing. (It was running very loud)
Upon disassembly, which was a little challenging with no YouTube’s to go on, I found significant the shaft turn to be very tight. Then the shaft entry into the motor housing was quite rusted.
Before I replace it, I have a few questions.
The rubber flat gasket surrounding the shaft doesn’t seem to seat to the housing. The flanges/blades on the insert in the pics are offset such that the gasket is recessed and doesn’t make contact with the housing. Also, there is a square gap in the bottom of the housing where dirt and bugs got in... I’m sure sand didn’t help the seals.
Are these two design elements normal? Seems like a bad design... the shaft seal to the wet side was fine.
Are these badly designed or am I unlucky.
unfortunately, it’s a few months out of warranty.
Mar 5, 2019
Tallahassee, FL
Forgot the pics.


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