Engine number written in pencil inside engine

[David Oslo]

During the process of completely stripping my engine I have discovered the engine number written in several places in pencil. Has anyone else come across this?

My prime suspect is a (documented) workshop visit in '92 to get the old girl out of her 15 year dry-storage hibernation. Thought being that the workshop had several 6-cyl engines on the go at once, and numbered the parts so as to not mix them on the bench.

The engine number is written on the inside of the front timing cover in the
'well' for the water pump impellor, and on the sides of all the pistons.

Of course I could be barking up the wrong tree, and in fact all engines coming from the factory had pencil markings on the pistons. Doubt it, given that I've never read of this phenonomem.

[PeterCrespin]

Those are parts that must stay with the given block and are highly likely to be reused so it makes sense, assuming they were ever stored/worked on apart. Pencil is graphite and is harmless when washed off although I didn't think normal pencil write on metal other than dull plating. May be some kind of special waxy pencil?

[Harold Lang]

Very much so. I remember noting four of the pistons still had the penciled engine number: R 5126 seen during an engine tear down in 1973. I wonder if they are still there now......

Harold Lang
885963

[David Oslo]

I do understand the relevance of the parts staying with the engine, just wondering if this was from factory (highly unlikely) or from a past rebuild.

Graphite is carbon. And carbon deposits do have a nice tendancy of sticking to cylinder heads and pistons. Just think of 'decoke' engine job. So by all means pencil markings will be visible and remain on grainy metal parts such as a pressure-die-cast timing cover or pistons.

In defence of the pencil, my engine has only done 1,500 miles since being opened last (in 1992). So it's no exactly been through a durabililty test. :D