should there be a bolt securing the water pump in the top left hand corner or is it a dowel,looks like there been a thread in there at some point but looks like its been damaged as the hole is smooth,also cant remember removing a bolt from there.

 

i took the water pump off my 4x4 last weekend,
i remember there was 4 bolts holding it on so going by your picture i'd say there should be a bolt in there

 

Should be a bolt there, a pain in the rs bolt, so shrouded hard to get to, replacing with a cap head(allen bolt) males life a lot easier.
tabetha