I have a 1988 F250, 351 engine. been running fine. Suddenly smoke is coming from right side of engine block (facing forward), from somewhere under valve cover. Can quite see exact location, but it's above the spark plugs. I'll have a mechanic look at it soon, but am curious as to any thoughts on what it might be.

 

 

I mean, cannot quite see origin point, not can. Valve cover gasket blew?

 

Have you checked your water level?? It could be a heater hose leaking onto the manifold. Is it an oil type smoke, or a hot water type smoke??

 

On an '88 F-250? It's GOTTA be oil from the valve cover gaskets! Just plan on replacing them, and you might do the oil pan at the same time. Silicone 1-piece gaskets with bolt-hole inserts are a LOT cheaper than they used to be.