Fixing pistons + valves

[gl0ckage]

Hey all, I have 2 spare engines, 1 has rust and mould looking crap in the valves and most likely in the cylinders - I previously took this one apart to get a bolt spark eroded out.

I also have another that burns oil - my guess is valves and pistons. Is that all i should be worrying about?

I want to fix both engines as i have my main GS and 2 projects which i will be sharing with you all very soon

Any tips n tricks i should be aware of? Obviously i have gone down half way through the engine to pull the top end off. havent ventured any further than that.

[sledge]

Rust in the cylinders??

Rebore or boat-anchor 

[gl0ckage]

Like I say of the water has penetrated in past the valves I'm going to assume it's rusting. I'll have to have a look when my garage arrives.