I've just taken my engine apart again for another rebuild and have noticed that on top of the block [where the head screws would screw into there are two faint circular scores marks in the metal. The piston sleeve also has half a circular score mark on top. Any idea what might cause this?
Maybe a rock fell in when you took the glow plug out? I'm not sure what you mean by "scores" though... Pctures would help alot!
Here you are, its quite hard to see as they are so small. Might need to hold control and press + and few times.
It looks like when you were putting the head on at a previous time the screw didn't line up with the hole and made those marks. They don't look inhibiting from the pics though.
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