Timing Chain Wheels Wear
 

Hi,

How would you determine if the chain wheels (camshaft and int shaft) are worn and require replacing?

Thanks Neven

The inspection will be by visual determination.
If the chain alignment is done properly when built there should be no problem
Bruce

Wear on the teeth can make them have a sharper point and also more wear at the roots of the teeth. Compare to a pic of a good/new one, it shouldn't be hard to tell. And obviously any chips or other wear/damage.

Thanks - yes that all makes sense. Just thought there might be some key measurement but I'll clean up the six I have and see if I a good pair

The gap between the left hand side idler arm and the outer cam housing gets smaller as the bottom of the sprocket teeth get worn. The chain doesn’t stretch. The sprockets themselves get “smaller” and the fixed length chain has to be accommodated by the extension of the hydraulic chain tensioner. Which pushes out the idler arm so that the tension is restored.

Net effect is the idler arm moves closer to the case.

Replacing the chain without new sprockets does not solve the problem of an extended hydraulic tensioner.

Some time back there was advice on this forum to lay new chains over the sprockets and attempt to lift a link. The more worn the sprocket teeth, the higher the link is able to lift away from the sprocket. I don't recall how much lift was acceptable.

andy