Have you try turning the engine "clockwise" and "slowly" manually?
If its a piston hitting the valves you will fill it.

I just tried to change a chain on a different car last weekend, it was bad, really really bad... It kept jumping and I lost the timing... Thne the pistons were hitting the valves.
I was lucky with trial and error I put the old chain back where it was ...

Just to say you will feel it if its a valve.
Good advice to take the pump out too, might not be the right one? just to clear all possibility.

__________________
E300TD year 2000. RUSTY SOLD
cost a fortune to maintain on the road
but run well on WVO
Second Merc died due to corrosion ( NOT rust) How can mercedes get away with that for so long?
Third lasted a month then went away...
Fourth now... Corroded too...

The crank will not move at all, but some play in the chain. The piston is not hitting the valve because it was up