This page describes some previously undocumented issues with LRG pumps. Our discussions while troubleshooting these problems are in the chat logs.
Examination of two of the three failed LRG pumps revealed rusted SS 316 springs (marked in red). The springs appeared, however, to still be intact. Unlike the failure described below, these pumps were only in operation intermittantly, and may have been idle for as long as two weeks under high-humidity conditions.
Examination of a similar failed pump (replaced 020107) suggests leakage and wear around what appears to be a small sensor access point not shown on the manufacturer's diagram. I've marked this in green on the figure.