My belt tensioner is stuck too, undo the tension bolt, it wouldn't slacken the belt.

Anyways had a long pry bar got the belt off.
Had used a M6 bolt with washers and a slightly socket to keep turning the brass plug that holds the timing chain plastic cover ( on right side of chain) , 2 of them, saw the lower one which is hidden behind the Thermostat housing.

Next step should be tilting the rngie to right so exhaust manif will slide out. At present the ex mani cannot clear.
To undo the manif /down tube bolt can be risky, as they get hot all the time and could be very stuck too.
These 190e are not exactly easy to work on because lacking of room to work.
My friend said, sometimes it could be valve seat got burned too, so not just valves alone.

Thanks everybody for being so helpful. And reading Edward the scissor hand performing a head job.

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