Cracked valve covers

[iozero]

I had to replace the valve cover gaskets on my 1980 450SL. During the operation I noticed that both covers had what appeared to be hairline cracks in them. The left one was the worst, next to the oil fill cap. At first I thought that these were part of the castings but they aren't. The car only has 45,000 miles on it and the valve covers have never been off of the car.

Thoughts? Is this a problem that should be fixed? There does not seem to be any oil leakage but I am perplexed why these would crack.

Hi Jim!
The covers on my 92' W140 300SEL has the same problems and was told by MB mechanic that the covers crack beacuse of the heat generated. Theres nothing you can do about it coz it will crack again after prolong driving with heat buildup. Can any members tell me if I am wrong and probably a solution coz everytime when the hood is up its an eye sore to see the beautiful machine spots a cracked valve cover.Cheers!

On Motronic injection cars a small amount of vaccum loss,
will make the car idle erratically.I cracked the cover
on my Bimmer,after valve adjustment due to over torquing.
Clauser1