FYI on motors that smoke

I see frequently someone mention that a motor smokes on startup, and everyone jumps right to bad rings or valve stem seals.
Neither may actually be the case and I will tell you why.

For one, a cylinder/s that misfire suck oil up through the rings and dump that oil right into an exhaust system that is hot from the cylinders that are running.
Sometimes smoking can be cured by making sure all cylinders are firing.

Another possibility is an intake gasket leak, that allows oil to get into the intake ports.

Also, valve cover leaks can soak between the heads and exhaust manifolds after shutdown, and burn off inside the exhaust when the engine is started again.

So let me say this one more time.
Smoking on startup is NOT always caused by rings or stem seals.

I just read three pages of “my motor smokes on startup and runs like crap”
But not one mention of the possibility that it smokes BECAUSE it runs like crap.

Ok, rant over. :D