560 sel 87, if the timing chain is tight after replacing the upper 3 guides and the tensioner and there is still a lot off chainslack "between the the camshafts" is the the bottom rail bad??

Have not replaced the chain yet and will do so now but the slack is present with all timing marks right on and crank is at 8 degrees After tdc., which is not too bad with old chain I guess, but I don't understand the above mentioned slack??

thanks
John1