Flattened lobe - how would I check for that? just measure the overall max dimension of the camshaft at each lobe? I can do that. Note, all appear to have a nice, smooth finish all the way around.
I did find two opposite bolts loose on the intake camshaft sprocket. Not really loose, as they weren't backed out any visible amount. But I tightened them maybe ten degrees without hardly any force with my 1/4" drive ratchet. Will put the proper 11 ft-lb on them before I run it next.
Is there any way that this can be timing chain related? PO suspected that, and thus replaced the timing chain tensioner. Any way to check for proper tension? | 
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