560sl water pump replacement now will not start

[sarastew]

I am a newbie that needs some help. I recently replaced the water pump on my '87 560sl and now cannot get the girl to start. The car ran great before I pulled the pump. Of course my focus has been on ignition timing as I had to remove the distributor to get the water pump off. I should also mention that I replaced spark plugs, spark plug wires, distributor cap and rotor while changing the water pump. I know there are many posts on proper distributor alignment and ignition timing on this forum and others. I have read as many as I could find, but still need help diagnosing my problem.

I have the factory service manual and followed the proper steps (or at least thought i did) for reinstalling the water pump and distributor.

1. Rotated the crank pulley to 0 degrees on the dampener. Looking inside the oil fill cap it appears the cam lobe is in the up position. I think originally I was 180 degrees out but corrected that issue.
2. Aligned the rotor with the mark on the distributor housing and reinstalled the distributor. Pointed to the #1 plug wire.
3. Double checked all plugs, wires, firing order, etc.

I had my wife crank the engine with a plug out and verified spark on the #1 plug. The plug did spark but I do not know what a strong or weak spark looks like (or if it matters). I smelled fuel on the plug so I am pretty sure I am getting fuel.

I should note that the engine does not turn over smoothly when attempting to start. The air intake burps a bit when cranking and the engine hiccups rather than turning over smoothly. The symptoms make me think of timing, but I hate to get fixated on that. Lastly, I should note that I rotated the engine counterclockwise slightly (quarter turn of the crank at most) when pulling the dampener. I have read some scary posts that this could cause the timing chain to jump, but I can't imagine a quarter turn could make this happen.

I am just looking for a fresh perspective on how to diagnose my issue.