Here's another possible failure mode:

On 2 pumps in a 617 engine, I've had the piston shatter. They are cast aluminum and have often wondered if anyone would be interested in a run of machined pistons from 6061 alloy.

__________________
Nate Stanley
(Currently Benzless)
1985 F-250 6.9l 170K
2009 SCION XB 36.5K
2003 LS430 78K
2012 Kubota B 2320