1997 Suburban has a bang and won't start

[fivemobbs]

I rebuilt the motor and now when trying to start it there is a banging when
turning it over and it won't start. It sounds like it coming from the driver's side.
What could be the problem?

[riverbanks]

The starter is loud,needs a shim,fix that before flexplate or starter gets ruined,and do you have a loose flexplate or torque converter?,you could pull the plugs,rotate engine by hand and listen

[Doug_Scott]

It sounds like you have left one convertor bolt loose and it is hitting the block when rotating.  You also appear to either have no spark plugs in it, or the valves a way too tight giving you no compression.

[fivemobbs]

55 minutes ago, Doug_Scott said:

It sounds like you have left one convertor bolt loose and it is hitting the block when rotating.  You also appear to either have no spark plugs in it, or the valves a way too tight giving you no compression.

You were dead on! I had to shim the converter and it was a little proud on a bolt. Also my dumba$$ forgot to lash the valves and they were over tight. I have compression and no clank. Thank you for your advice.

[Doug_Scott]

You sound surprised.