Rule of nine

[Army]

@Derek UK

I don't have pictures of the wear I've seen (well I'm fiarly sure I don't - I will check)

I have seen the following wear => Much like the shadows you can see on a worn cylinder bore I've seen patches on rocker arm polished surfaces where the softer core metal is showing through.

I've found this on abused engines that probably haven't had frequent oil changes.

The polished surfaces (where there has been contact) tend to be dull and scratched when oil changes have not been done for ages

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I've also seen more prominent wear through hardened surfaces where there has probably been rust problems. I can't remember which forum it was - but recently I remember a thread with a "can I use a rusty camshaft" question. I didn't respond. The problem with rust is that it is as soft as **** and so from a spot of rust you can get a chipping-like wearing propagation of wear across the hardened surface.

Rust ain't great.