Does the engine have solid or hydraulic lifters? It sounds like a hydraulic cam that somebody has adjusted like a solid lift engine. BTW, it's idling WAY too fast to run it with the valve cover off! 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!
It's not uncommon for a hydraulic lifter that sits for awhile with the valve held open to leak down all the way. 235's are notorious for lifters collapsing and taking a long time to pump back up, especially with the replacement lifters that are available now. I'm working on a project to sleeve down the lifter bores a little and run hydraulic lifters for MOPAR/Ford/AMC engines instead of the unreliable Chevy stovebolt hydraulics. 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!