Timing Chain??
 

87 560 SEL 235000 miles, bought with 210000 mile on it.

How do I know if it needs a timing chain or if it has been replaced??

Still fighting the initial start up rough idle.

Thanks
john 1

john,you will need to remove both valve covers and turn over the engine by hand until you reach tdc.now slowly move the engine until the mark on the drivers camshaft lines up.now look at the timing marks on the crank front pulley and see how far past tdc the pointer is.this will tell you how much stretch in the chain.

Also, I would inspect your chain guide rails. They start life as a light cream colour.. If they are looking Dark brown it's most likely time. Also, your cam tower oiler tube clips. They start life as a medium brown but with age they almost turn black. 8$ part that can eat $$$ worth of cam/towers.

Have heads ever been done on your car? Ever take a compression test? By 200K stock valve guides are toast.

Jonathan