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Impeller rubbing on diffuser
- Thread starter Chuck R
- Start date
Chuck I would check the mounting between motor and seal plate, sometimes vibrations pulls them apart, in turn causes the impeller to rub the diffuser more on one side. When you have the diffuser off, and everything apart, you can spin the impeller slowly making sure it’s completely parallel to the seal plate.
ferretbone
In The Industry
In this order.
1.The shaft seal is not in correctly, or flush (tight enough) or wrong size.
2.The impellar threads that thread on to the shaft are cross threaded or damaged. Some are plastic, and some are brass.
3.The diffuser is not mounted tight enough, or missing a screw. Or sometimes once in awhile its mounted and tightened down to tight.
4.The seal plate rivets where the diffuers screws go into are warped, damaged, rusted, and the diffuser screws seems to screw in tight but are not really screwed in at all. Rather jammed in.
5.The seal plate is not mounted tight enough to the motor. losen the bolts a little and tap the seal plate with a hammer while re tightening to bolts.
The motor shaft being bent is a unicorn, and probably worth money if you find one.
1.The shaft seal is not in correctly, or flush (tight enough) or wrong size.
2.The impellar threads that thread on to the shaft are cross threaded or damaged. Some are plastic, and some are brass.
3.The diffuser is not mounted tight enough, or missing a screw. Or sometimes once in awhile its mounted and tightened down to tight.
4.The seal plate rivets where the diffuers screws go into are warped, damaged, rusted, and the diffuser screws seems to screw in tight but are not really screwed in at all. Rather jammed in.
5.The seal plate is not mounted tight enough to the motor. losen the bolts a little and tap the seal plate with a hammer while re tightening to bolts.
The motor shaft being bent is a unicorn, and probably worth money if you find one.
This pump motor is the original and is the first time it has been apart. The impeller is definitely ”off center”. When removed, I can see some corrosion on the piece that holds the shaft in place. Is that the shaft seal? Would failure of that seal cause the error in alignment between the diffuser and impeller.
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You can flip the motor electrical side down and spin the impeller by hand looking at the gap between impeller and seal plate. If it’s at an angle Or cocked on one side even when you spin it, it’s the motor not aligned with seal plate. If that lopsided part spins with the impeller the impeller is warped or shaft is. But like previous posts bent shaft is rare, I’ve never seen it, only heard of it.
Remove the impeller and take the seal plate off of the motor.
Show the seal plate from the back.
Show the seal plate from the back.
unbolting the seal plate while diffuser is attached and tapping it then manually spinning the shaft until i didnt hear any rubbing fixed it for me. Thank you so much for the "in this order"
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