So, I'm checking the timing of my van before we leave on our trip this
weekend and the engine has a bit of a clatter coming from it.  I can't
exactly pinpoint where its coming from but I'm wondering if perhaps I have
the valves set too loose.  If I had them set a hair too loose, would I be
able to hear it?

If its not the vavles, what else could it be.  It sounds like its from the
engine itself and not a peripheral (like the alternator or waterpump).

thanks for any ideas,
blake