After running for a little while, my 307 smokes a little. I can't find any leak or burning hose. It does not have a burning smell but more or less something getting hot. It seems to be coming from down by the transmission fluid fill tube. Any ideas? Thanks.

 

I had a 69 Buick skylark the trans cooler line had contacted something down by the bellhousing and wore though, just a pin hole. It did not leak except under pressure, I took the trans out of that car twice before i found that cotten picken line, but by then it had gotten large enough to leak static an I was able to trace the leak. Probably something else, but worth a closer look.

 

Try seeing if it's Valve Cover Gasket

 

Do you see any kind kind of fluid residue? Is anything leaking on the exhaust?