Wear mark on underside of valve cover

Going through the bike compiling parts, assesing what needs to be done, etc. Pulled the valve cover because I have to replace the gasket, on the underside of the valve cover there appears to be about a 1/2" long scratch or rub mark where it appears that the cam chain in the middle has rubbed on the valve cover. Should I be worried? Maybe it was overreved at some point and hit? Cam chain tensioner gone bad?

 

Chain tension has been or IS loose.

If there is ANY play at all in the chain, get it tensioned up.
If you have the auto tensioner, they can be coaxed into working.

Remove all 4 plugs and left side cover.

Get a 19mm wrench on the crank flat nut, rotate slowly clockwise (motor turning backwards) 2 full rotations and stop smooth.

While having a friend tap with a wooden hammer handle on the tensioner bolt, quickly spin the motor counterclockwise (motor forward) about 3/4 turn. Repeat a few times, check your tension.

 

Thanks for the tip and instructions! I'm assuming that these instructions are for the automatic tensioner? My Seca 750 (according to everything I have read and have been told) has the automatic tensioner, so I'm assuming your instructions are for coaxing it into working if it's stuck? Thanks again!