6480 dropped a valve

[Massey mad]

As title suggests our perkins engine 6480 has dropped a valve she's always been religiously serviced always owner driven on 6.5k hours... it had new injectors fitted around 50hrs before this happened which cost around 3k (failry Common procedure on these engines) but mks this has happened which has knackered the head and a piston... anyone care to throw any light or thoughts on what could've caused it? Many thanks

 

[box]

Intake or exhaust valve? Has the valve head broken off or has the whole thing dropped?

A few possible reasons off the top of my head (not that I'm overly familiar with the 1106 Perkins engine):
-Bad luck/part failure
-Bad injector
-Weak or broken valve spring
-Foreign object entered engine during injector replacement
-Engine over rev
-Incorrect valve clearance

The first thing I'd be doing is getting those "new" injectors tested - ideally by an independent party....just in case.
Next thing, check valve clearances and valve height/depth and spring height/springyness.

A good look at the broken end of the valve stem might provide some clues if it's managed to stay in the head?

 

[Nearly]

@masseybreaker

 

[startinghandle]

why were injectors replaced?
Was there running problems ?
There could be more damage like bent conrod

 

[startinghandle]

Was anything else done at same time?