340 runninng lean and overheating

Thank you both of you, I will have a look aty the timing later today :)
I just cant understand how the timing has goten so messed up, when I supposedly did nothing to cahnge it :/

The engine ferries come into your shop at night and screw with stuff. It’s either them, or my wife. But I can’t catch either, so I can’t say for sure which it is.

Sometimes they just break in the shop or in the trailer.