replacement engine components undergoing hot tank cleansing

before teardown cylinder 3 seemed to have poor compression

what was found was all injectors had fine dust in head pocket--and this material had hardened into
weak cement

copper compression washer separating injector body from head had lifted in cylinder 3 pocket--this is evident in pics linked

these injectors should have a boot providing some barrier to foreign material entry into head pocket

and--as seen in pics---failure of o-ring on injector shaft is evident in all

https://postimg.cc/gallery/1jqj0y83c/

Its possible that the injectors were removed at one time, then put back in without replacing the copper washers and o rings. That would cause the failure you describe.

At 160k miles when I pulled my head, the injector holes looked great. In fact, the o rings had such a tight seal that they were quite difficult to pull out.

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U.S. Army Retired

The o-ring is more for balancing them and keeping them level than it is a debris seal. I have found plenty of CRDs where the bottom of the injector is completely encased in crap - usually oily dirt. Dirt and debris gets on top of the engine from the windshield seal or from "helpful" wildlife who like making nests on the top of the warm engine in the winter... And then it degrades and the particles get ever smaller and mix with the oil leak from the CCV as they fall into the injector wells. Eventually this combines with the vibration and heat to form a solid mass of sludge.

On engines that lack the CCV leak, the same process happens but manages to remain dry for the most part.

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