Cooling head leak?

[savage25matt]

I went out to tune and got frustrated.... the mill seemed lean at first, then as it came to temp it seemed too rich, so I adjusted accordingly, then it leaned way out...

Then I noticed a TON of baked on crap on the exhaust manifold, took it inside and found that the bottom of the cooling head looks "wet"

Any idea what might cause this?

I double checked the cooling head screws and glow plug before I went out... everything is tight...

 

[JoeGuam]

Your carb might not be sitting properly or oring at the carb is no good. How i know it happened to me.