1.9dg number 4 cyclinder big end faliure

[youthy giblets]

Recently had big end faliure on my 1.9dg engine. on strip down the crank appeared to be absolutely spot on and measured up ok however the shell on number 4 con rod side was badly pitted into copper luckily i heard it quietly and inspected straight away. the cap side shell was near perfect as were all other cyclinders blew through all oil ways all were clear and i havent had any coolant/oil contamination issues

Do many suffer from this and if so y?

[kevtherev]

No it's not common at all
It may be a component failure, or at some point in the engines life it has been abused, either with poor oil or no oil and filter changes, you're just the unfortunate recipient of this long past abuse.

[ghost123uk]

Sorry to hear of your misfortune

Are you going to re-build it ?

[Oldiebut goodie]

Maybe some numpty put new shells on previously and lost one and left an old one in. I've never seen that on any engine before - you would expect to see both shells with pretty much the same amount of wear.

[youthy giblets]

Engine is already re-built and re-fitted in the van tonight just exhausts to re-fit and hopefully all good as new
a pic of the offending shell as i say other side was as new this is the rod side shell and crank was as smooth as ababys back side. All shells were stamped with vw logo and part number so unlikely to have been changed and mis matched

[Oldiebut goodie]

That's nasty, never seen just one like that. It must have been a bad'un right from the start. Have you put a new set of shells in now?

[..lee..]

looks like component failure to me. never seen a shell degrade like that before.