Failed cam follower

[brian buttimore]

Hi All,

Picture of a failure of a cam follower bucket that caused some damage.

Cam followers all worn 0.0005" under size and show signs of mushrooming.

Picture of the failed follower and another follower from same head shows heavy circular wear rings .

my question is has anyone heard of a follower seizing or jamming in their bore to cause this type of failure.

Welcome your thoughts.

Brian

[Seaking]

Brain
I have seen some that have barrelled I think it is a normal pattern of wear as they rotate as well as move up and down its the moving part that wears quicker than the fixed part even though the heads are softer. the ones that I saw where replaced with new. With no ill effects in fact the tapping stopped. Never seen one cracked though
Cheers Glenn

[flying farmer]

looks like the top has come clean off the cracked one, never seen one like that. I wonder if it had a manufacturing flaw?
As Glenn says, they normally develop a waist in the middle, sometimes a new set of followers fit ok, sometimes oversize followers are needed after machining the worn bores. I had one head that wore new followers very quickly due to abrasive particles embedded in the alloy, had to fit +20 buckets but the rebore got rid of the abrasive crap.
Neil