It is easy to add not enough  shim thickness on the crankshaft.
Check the  crankshaft for end play. Loosen the Flywheel /torque
converter plate
then see if it turns then.  Been there done that.  When testing for
crankshaft
shim thickness it is easy to add not enough shims  because we don't
tighten the
the flywheel fully during testing / adjusting.
      Best of luck with your projekt
Midwesty

On 12/31/2015 4:30 AM, John Rodgers wrote:
> Engine turns beautifully by hand on the bench. Put the new AMC hesds on
> with all parts assembled, torque them down,  and the beenengine won't turn.
>
> Removed the heads twice, still no joy. Sounds like a valve stuck in a guide
> to me.
>
> Any body else ever had this problem or got an educated opinion?
>
> Thanks.
>
> John
>