Here's a quick way to check for hydraulics. Remove the valve cover, and get a valve close to fully closed. Clamp a pair of vise grips on the rocker arm, and exert a firm, steady pressure toward the pushrod for a couple of minutes. If the lifter is hydraulic, the clearance between the rocker arm and the valve stem will slowly increase until there's about a 1/8" gap above the valve stem. As soon as the engine is re-started, the lifter will pump up to zero clearance again.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!