I'm replacing a crank and connecting rods in a 2.4L DOHC motor in a 2002. The only question i have is about the chain driven internal counter balance on the bottom of the motor. I can not find this assembly anywhere in my manuals. I'm assumming on the purpose of the assembly. The front of the sproket has a mark. I didn't know were this mark going in reference to the crank. Can any help me?

Thanks

Jason