CM2250/CM2350 Fuel Pump

[SquareOne]

After seeing one in person opened up, I would like to know how they actually fail. Of the carnage pics i've seen from this site and what I've read, it looks to me like the rollers and cam lobes were oil starved...just an educated guess. If you have an engine that's heavily sooted, wouldn't you think that it would starve the pump of lube oil if the passages were even slightly restricted?

I mean, the plungers failing.. wouldn't that strictly be a fueling issue? The movement of the plungers is very little so even if they were to get stuck in the extended position, it seems like it would starve the engine for fuel...not destroy the cam/rollers. The spring will keep the roller contacting the cam at all times so a plunger stuck closed should also not result in destruction. Maybe when the ceramic ones failed, they shattered and thats where the damage started? I would just like to understand this more.


This is all just an assumption as I have no base to what I'm saying other than what I observed when opening the fuel pump up. Maybe the engine builders can chime in with there thoughts? What was the condition of the barrel/plungers when a fuelpump failed? Seems like they would still have to be pumping fuel in order for the engine to run long enough to tear itself up?

- Has anyone seen the same fuel pump failure with the updated tappets? Makes me again wonder if majority of the issue was with the brass roller pins in the older tappet design? As the pin fails it would certainly stop the roller thus dragging it along the cam lobe....we all know what friction does, and in a hurry. It seems like that would make sense. If the roller and cam lobe was substantially damaged (as in littering the engine with debris), I would imagine the erratic movement of the tappet would then damage the plunger....so it would appear as if the plunger was the culprit when it was actually the failed roller pin that started it all! - Dunno...sounds like a decent theory lol