my 93 d150 5.2,has i guess i would say noise when i shut it off??
sounds like the valve springs are tapping,when it is cooling down.
sound like small hammer taps that alternate from left side to right side??
it runs extremely strong,128,000 miles, anyone know what? or why this is doing this? i have owned other 318 magnums years ago,never heard this before,could they have been changed at one time?? thank you

 

I obviously can't hear what you are hearing but this is a possibility. You can get a snapping/clicking sound from the exhaust manifolds as an engine cools due to metal contraction. Mine does this and always has.

 

thanks seal, i also get the same noise if i turn the engine over by hand,via damper bolt,when cold or hot. it just seem like its valve spring tension,but do not hear anything when running.
does not affect the way it runs or power,just cant figure why it is doing this,just need piece of mind thank you