Weird noise coming from engine
 

I have a 1990 190E 2.6L and when I start the engine I hear a weird noise.....hard to explain sort of like a low "clum-clum-clum" noise coming from the engine. I have a leaky valve cover gasket for sure that I need to replace, so while I have that of I would like to know if anyone has any idea of what it could be under there making that noise and what I need to do to resolve it. Thank you for your help in advance.

Unfortunately, noises and vibrations are BY FAR the most difficult things to diagnose over the internet.

Try localize the area of the noise.

Well I know that its coming from the crankcase where I pour in my oil. Just not sure what it could be.

Belt?

No, coming from inside the valve body. I just took off the valve cover, cleaning it up a bit. I need to order a new gasket and distributor cap