How did injector get damaged?

[Sam Johnson]

Injector tip is blunted and shiny, cyl 8 is only one like that on driver side. Engine started to shake and then it got worse. Stopped and towed home, ran diagnostics with Autoingenuity. Contribution balance fault cyl 4 & 8, misfire cyl 4. Pulled those injectors and found this:

Picasa Web Albums - TAJ1989 - Powerstroke I...


Picasa Web Albums - TAJ1989 - Powerstroke I...

Is there any way to investigate without pulling the head?

Is there a camshaft timing problem that could cause physical contact with injector tip?

Is it possible for injector to have been damaged when installed and for engine to still have run 100,000 miles and for tip to not have carbon like sides of injector?

OK, is the rest of the glow plug inside the cylinder?
Picasa Web Albums - TAJ1989 - Powerstroke I...

Any suggestions would be appreciated.

Thanks in advance.

[Robsr]

Wow! could you hear it hammering? was it hammering still when you tore it apart? probably beat the h*** out of the piston, and head. not sure i wouldn't pull the head and take a good look.

[dannyboy950]

There should not be anyway for this to happen. The piston to head clearance is to great for this to happen on its own. A foreign object ( glow plug tip?) would have to bridge the gap between the top of the piston and the head surface for the injector tip to be hit and flattened. It only sticks past the head surface by about a 1/16 of an inch or less. The piston to head clearance is about a 1/4 of an inch.

In 40 years of working on diesel engines I seen this only once before and it had a piece of broken valve on top the piston. But man ya could hear that thing hammerin from a block away.

[Sam Johnson]

Originally Posted by dannyboy950

There should not be anyway for this to happen. The piston to head clearance is to great for this to happen on its own. A foreign object ( glow plug tip?) would have to bridge the gap between the top of the piston and the head surface for the injector tip to be hit and flattened. It only sticks past the head surface by about a 1/16 of an inch or less. The piston to head clearance is about a 1/4 of an inch.

In 40 years of working on diesel engines I seen this only once before and it had a piece of broken valve on top the piston. But man ya could hear that thing hammerin from a block away.

You guessed it, found that only a hollow tube sits where the whole glow plug used to be. Going to pull the head next to see whether I'm rebuilding or starting with another motor. Was 2 months and 690 miles out of warranty. Do glow plugs often fail or am I just "really lucky"?

[forddieseldoctor]

Wow that sucks. I've never seen or heard of that happening before.