Is it normal or should I start thinking about replacing it soon ?
I have two service manuals Haynes and Autobooks and both don’t give clear answers to my questions.
Since where is no actual chain tensioner , the only thing what adjusts the chain tension is a rubber ring what goes between the teeth on the small sprocket. (#6 on the diagram)


Am I right , or I am missing something ?
Sinse my car is 1973 that ring is probably dried out and it is not doing it’s job anymore.
The questions I have :
Will replacing the rubber ring fix this problem or should I replace the chain , gears and the rubber ring all together ?
Is it possible to remove front cover without taking the oil pan off?
I found few chain and sprockets sets for sale, but they are not the same.
Here is the original

Some chains are just plain, but others have some kind of teeth sticking out , maybe to pick up some oil, or for some other reason.




But none of them shows that rubber tensioner ring , or it is already preinstalled on the sprocket ?
So which one should I get , the one with teeth or the one without the teeth , or it doesn’t matter ?
Any advice will help.