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But version 5.3

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Originally posted by Don Rainey:
I am with Ralph, the prior to failure data in the powerpoint screams bearing failure in progress to me. The persisent overheating suggests a thrust problem, and plastic cages do not cope well with such situations. Avoid plastic bearing cages like the plague.....

And with respect to the fact that the frequencies - which certainly have the appearance of a severe bearing fault - don't line up with calculated values, remember that the bearing in question is an angular contact bearing, and in the presence of excessive thrust loads, and a plastic cage, the contact actually changes from the standard, which of course modifies the defect frequencies.....

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Originally posted by Turbine:

We changed the bearing today and can't see any defect from the bearing.

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Originally posted by Turbine:
Thanks all that help me!
We changed the bearing today and can't see any defect from the bearing.
A new bearing was installed and the pump is normal now.

Attached the spectrums before and after failure for any body need to learn.

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Originally posted by Alex J:
I have seen similar cases in the past. If you go back and display spectrum in g's up to 5kHz you'll see a hump at higher frequencies ~4kHz. These are caused by numerous micro cracks developing on the races. At this stage energy is low and looking in velocity spectrum you'll not see it. When these micro cracks develop into bigger ones the hump on the spectrum starts shifting into lower frequencies (less bigger cracks on the races). Some time the edges of these cracks are getting smoothed out by the passing balls and vibration level drops. It's a major warning signal that next jump will be exponential.
You mentioned hot bearings. Do you have adequate oil viscosity at the operating temperature? Maybe you should try synthetic oil with higher VI? The oil mist should also lower your bearing temperature.