Can you bend the valves via a breaker bar on the crank pulley with the cam gears not in proper orientation? One of the cam gears already spun around due to the timing belt not having tension, was going in for a timing belt swap anyways and had a heck of a time getting the crank bolt to loosen. Did several rotations of the crankshaft before the bolt would finally budge. The engine is NOT in a vehicle so it wasn't running like this...
Yes, I manually rotated a crank years ago after lining up cam gear marks to center valve cover arrows. Resulted in bent front intake valves and once the starter got involved, a valve snapped off and locked against the piston.
Moral: Some FSM diagrams are misleading, and it's possible to bend valves by hand.
Just in case someone searches for a similar topic. I did NOT bend any valves doing this, most shops I spoke to about this topic said they have heard of it but never replicated it themselves.
How do you know you didn't bend any valves? Unless you removed the valves and spun them at least a couple could be slightly bent. Almost every head off modified/molested cars I've torn apart had a couple valves that were slightly bent. Most visually look fine and the engine will still show decent compression and run fine though.
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